Create README.md in tests

SVGHMI: update generated xslt, and svghmi test project files

SVGHMI: Add pushbutton widget, that can take reflect short press in variable, but has no garantee on consistency.

SVGHMI: Fixed support for frequency parsing in widget label

Merge

SVGHMI: update generated xslt

SVGHMI test: add special commandline to launch chromium as new intependent window, without GPU acceleration.

SVGHMI: add syntax for widget update frequency in widget label: HMI:WidgetType|freq:arg0:arg1@path

OPC-UA client: "static" class was forgotten for open62541 client structure preventing multiple client.

OPC-UA: cosmetic fix and armless typo

Merged default in wxPython4, include runtimeLists

Merge

SVGHMI: added ListSwitch widget

Merged RuntimeLists branch

Close RuntimeLists branch

Fix bug introduced in previous commit : dual link list wasn't append and remove wasn't implemented correctly. Removed debug code, enhanced variable names and comments.

SVGHMI: optimization of C part : stop traversing the whole HMI tree, use dual linked list for subscriptions and single linked list for changes from HMI. Intermediate commit, still crashing in some cases.

Xenomai runtime: ensure that __DEBUG global variable is set when resuming debug.

SVGHMI: Adapt svghmi.c to changes in UnpackVar

Runtime: Now retain uses a list based on data available in VARIABLES.csv instead of traversing the whole instance tree looking for RETAIN flag.

RUNTIME: Variable forcing now uses limited list and buffer instead of systematical instance tree traversal and in-tree "fvalue" to keep track of forced value for pointed variables (external, located). Pointer swapping is performed when forcing externals and located, with backup being restored when forcing is reset. Retain still uses tree traversal.

RUNTIME: Variable trace now uses limited list and buffer instead of flags in instance tree that was requiring systematical instance tree traversal, and worst size buffer. Forcing and retain still use tree traversal.

SVGHMI: more accurate filtering of elements to unlink or not

OPC-UA client: generated code now take UA_Variants on the stack directly, avoid useless allocation on write, and unalloc implicitely allocated data on read

OPC-UA client: generated code now take UA_Variants on the stack directly, avoid useless allocation on write, and unalloc implicitely allocated data on read

IDE: Tutorial/Example menu was broken : path of project being open was the same for all menu entries.

IDE: Tutorial/Example menu was broken, probably after a merge. Menu (and corresponding code) was duplicated. Also, path of project beeing open was the same for all menu entries.

Fix bug when updating data in variable panel.

Grid event naming CHANGE->CHANGING was wrong. CHANGE->CHANGED is the way to go.

SVGHMI: update tests/evghmi to reflect/test latest changes. update generated XSLT.

SVGHMI: multiple non significant changes: doc fixes, modern style access to attributes, enforce double quotes around member name in object literals.

SVGHMI: Changes /CURRENT_PAGE_* behaviour to prevent problem whith multiclient : all clients were switching page when one was jumping.
- now PLC have to prefix page name with "!" to order page switch.
- HMI do not prefix with "!" when jumping, this avoiding looping incidently
- In case of multiple client:
CURRENT_PAGE reflects current page of last client hwo did jump
Setting CURRENT_PAGE with "!" affects all clients simultaneously

SVGHMI: changes that should fix some corner cases about unlinking and discardable element that still didn't show until now.
- list that would have been declared in some groups could have been discarded.
- elements to be unlinked were comuted based on filtering $hmi_elements, whereas $hmi_widget already filtered list

SVGHMI: update generated XSLT

merged

SVGHMI: add CURRENT_PAGE_{location} global variable to reflect currently visible page. If PLC wites some valid page reference in that variable, it triggers page switch. Additionally, fixed /HEARTBEAT being subscribed systematically by JS code even when wtchdog is not enabled.

Follow-up on 83ed4ea362db 'IDE: prevent invoking matiec when IEC code did not change since last build' : build unconditionally after clean

merged

OPC-UA: fix types in model not being preserved after reload of CSV file, leading to exception when changing selection lists content.

OPC-UA: Removed more "LocalizedText()", this time in selected variable list

IDE: prevent invoking matiec when IEC code did not change since last build.

SVGHMI: prevent systematic rebuild when there are multiple instances of SVGHMI CTN.

SVGHMI: optimize HMI tree handling C code to lower CPU usage when traversing large trees

merged

SVGHMI: prevents watchdog being triggered when SVGHMI is empty.

Backed out changeset c646a1f0fb0b - was on wrong branch

Make OPC-UA client compatible with wxPython3, util wxPython4 branch deserve to be merged

Make OPC-UA client compatible with wxPython3, util wxPython4 branch deserve to be merged

IDE: Enforce wxPython3 menu appending syntax in default branch... (Fixes exception at startup)

OPCUA: fix display names appearing with a "LocalizedText(" prefix when browsing localized server.

OPCUA: Add browsing of variables exposed by client when selecting location from variable panel.

OPCUA client: fix handling of string type Node Identifier

Add OPC-UA simple synchronous client extension.

This extension uses python-opcua to growse server nodes, and generates runtime C code that use open62541.
- python-opcua must be available in python path (i.e. "import opcua" must succeed). Can be installed from pypi with "python2 -m pip install opcua --user" .
- at build time, open62541 is expected to be build in "open62541" directory, aside "beremiz" directory.

SVGHMI: update test/svghmi to reflect latest changes

SVGHMI: Update generated xslt

SVGHMI: remove "value" element in meter and circularbar widget. Adding support for printf like formating make widget label too heavy. It is better to use Display widget instead.

SVGHMI: Move sprintf.js out of widget_display.ysl2 since it is used in other widgets as well

Dropped SVGUI, deprecated and replaced by SVGHMI. Transformed traffic_lights exemple so that it uses SVGHMI instead.

SVGHMI: Update generated XSLT (PathSlider widget)

SVGHMI: simplication in ScrollBar widget JS code

SVGHMI: Added PathSlider widget