SVGHMI: propagate default local variables (HMI_LOCAL, PAGE_LOCAL) to widgets at startup

SVGHMI: Update generated XSLT

SVGHMI: HMI:DropDown:#langs@lang now automatically shows human readable list of languages. tests/svghmi_i18n updated accordingly.

SVGHMI: Add a simple i18n test

SVGHMI: Prevent Dropdown widget to mak exception whe value out of range

SVGHMI: removed dead code

SVGHMI: Add "lang" permament persistent HMI_LOCAL variable to reflect selected language, apply stored language choice at startup and make it always subscribed to a pseudo widget (as for hearbeat) that apply language choice when it changes.

SVGHMI: Added HMI:VarInitPersistent to initialize persistent HMI_LOCAL and PAGE_LOCAL variables, stored as cookies in browser.

SVGHMI: Enforce formating HMI_LOCAL and PAGE_LOCAL variables until the end of variable name

SVGHMI: generate JS translation literals so that it is possible to also translate uses of texts, and added JS code that apply translations to tspans

SVGHMI: widget activable elements : moved code to wher it belongs, rewrote cleaner

SVGHMI: update generated XSLT

Merged

SVGHMI: make a copy of tests/svghmi as test/svghmi_widget because too crowded since having pages for widget documentation. Strip those pages from tests/svghmi, so that it
is more light for regular testing.

SVGHMI: Prevent excluded widget to appear in generated pages' widget list.

SVGHMI: Remove recursive walk in parsed widget to find unique type and use xsl:key instead.

SVGHMI: Fix browser side exception when some widget are not used, and are then discarded and not present in final SVG. In that case JS code was still making reference to discarded widget elements and was raising exception at init.

SVGHMI : removed support for changing keyboard position and showing at user defined location. Feature was problematic in many respect.

SVGHMI: Make an error when pages are nested

SVGHMI: i18n: finished passing back translated messaged to xslt proc, finished template to generate corresponding javascript literals.

SVGHMI: i18n: various fixes about unicode encoding and converting translation result back to XML to feed xslt processor

SVGHMI: i18n: better warning messages, more explicit.

SVGHMI: i18n: now loads PO filesand match translation against catalog. Refactored a bit to move i18n related code in i18n.py

SVGHMI: still WIP, now POT file is properly generated with utf-8 encoding and POEdit is launched when pressing button.

Docutil : reworked Inkscape launching and path resolution in docsvg.py

merge

Removed harmful assert in ProcessLogger.

ProcessLogger was having an assert in constructor when missing logger, leading to systematic exception when testing options accepted by compiler. This exception was silenced in ProjectController, and then MatIEC was always called without options.

SVGHMI: Intermediate commit while implementing i18n. WIP.

SVGHMI: Jump widget: switch to class based declaraion, and add some TODO comments to prepare for jump to relative page being selected through a DropDown widget.

SVGHMI: intermediate state of test/svghmi's SVG for backup... WIP