Improve support for C++ project.

[xkam1x]

Issue

The template offers good support for C projects and attempts to include C++ projects as well.

Unfortunately, when using C++ files, the rules.mk fails to include C++ standard library -lstdc++ which can result in undefined reference to various objects.

Fix

You can add a few lines to rules.mk to check for CXXFILES and add the -lstdc++ if necessary.

Example Fix

100	100	LDLIBS += -Wl,--start-group -lc -lgcc -lnosys -Wl,--end-group
101	101	
	102	+ ifneq ($(strip $(CXXFILES)),)
	103	+ LDLIBS += -lstdc++
	104	+ endif
	105	+
102	106	# Burn in legacy hell fortran modula pascal yacc idontevenwat