Trying to get better logging/display of exceptions at runtime's startup

Changed way to deal with extensions arguments (-e) so that path and filename are stored independently and accessible for extensions themselves.

Textviewer : moved call to Colourise in a better place, so that ST highlighting gets also updated when typing in some case, not only IL

Main runtime template C code : Added HAVE_RETAIN preprocessor definition for customized build to signal it provides IEC-61131 Retain memory handling function. Removed targets/Xenomai/plc_Xenomai_noretain.c, now useless.

Clarify licensing, and packaging of runtime only files :
- moved and split targets/typemapping.py into runtime/typemapping.py and runtime/loglevels.py
- added runtime_files.list pointing to files necessary for runtime, and referring to runtime license

Enforced check_source.sh pep8 and pylint rules.

runtime/WAMP: Fixed secret loading into configuration. Fixed secret commandline switch handling.

runtime/WAMP : was 'Added time print on session left.' from dporopat. Purpose is to log (dis/re)connection, to help debugging connection problem

runtime/Wamp : adapt to unicode being enforced in latest crossbar API. Updated some documentation, to explain why there is unused definitions like SubscribedEvents or DoOnJoin.

Extend python<->PLC global variable description "GlobalDesc" to support Initial value setting.

Rebased from dporopat change "add initial value to runtime.py file", which means :
- GlobalDesc is used by some customized beremiz python runtime
- Those runtimes need to know what is initial value of these special variables

update tests/wamp README file, based on changes from dporopat.

Fixed WAMP test (crossbar confile upgrade and use same ID on both PLC and IDE side)

Fixed changes from dporopat and agregorcic about WAMP CRA and config.

WAMP runtime : changes from dporopat and agregorcic, adding CRA (-s) and changed way to load WAMP conf (-c)
- added Challenge Response Authentication,
- use -s commandline switch to give the shared secret.
- WAMP configuration now either given as -c commandline switch
or taken as default wampconf.json in project files.

Set WAMP registration option so that reconnecting while earlier session still didn't timeout is possible (in case of connection lost, for example).

More canonical overload of ReconnectingClientFactory (according twisted doc)

non significant print syntax change. ready for py3.

whitespace cosmetic for pep8

Added arbitrary timeout on Pyro, to force it to free memory after disconnect.

Moved code from to Beremiz_service.py Server class Start method to Loop method to allow customisation by hot patching. Also renamed Stop method as _stop and use Restart instead of Stop from everywhere else to make it clear that _stop actually does restart...

enforce PEP8 in previous commit

replaced normal panel with scrolled panel under project properties

fix missing root in empty search results panel

add possibility to specify subprocess stdout encoding

fix deadlock if method kill() is called after process is already finished

fix pylint py3k conversion warning: "(no-absolute-import) import missing `from __future__ import absolute_import`"

make CanFestival to be at the expected place in bitbucket pipelines container

fix pylint error '(unsubscriptable-object) Value 'X' is unsubscriptable'

fix pylint warning '(bad-continuation) Wrong hanging indentation before block'

force all python source code to have LF line ending