beremiz

make attribute CFLAGS and LDFLAGS optional and add default empty value

Actually CFLAGS and LDFLAGS are not required and can be empty.
Without default empty value if target platform in project settings was
set to "Linux" CFLAGS and LDFLAGS was initialized with NoneType.
The result was broken build and it wasn't to save/load project with
such settings.

Traceback (most recent call last):
File "/home/developer/WorkData/PLC/beremiz/beremiz/ProjectController.py", line 956, in _Build
if not builder.build() :
File "/home/developer/WorkData/PLC/beremiz/beremiz/targets/toolchain_gcc.py", line 96, in build
Builder_CFLAGS = ' '.join(self.getBuilderCFLAGS())
TypeError: sequence item 0: expected string, NoneType found
This project contains wamp client config to be loaded at runtime startup.
project_files/wampconf.json
wampconf.json is in "Project Files", so it is copied to runtime's working directory, and then loaded after program transfer + runtime restart.
Otherwise, wamp config file path can be forced :
./Beremiz_service.py -c /path/to/my/wampconf.json /working/dir
Crossbar test router configuration is available in .crossbar directory. Start with :
crossbar -d start