travis: run test_matchcompiler.py
travis: move CHECK_INTERNAL check up, remove "SRCDIR=build VERIFY=1" job in favor of "MAKEFLAGS="HAVE_RULES=yes" SRCDIR=build VERIFY=1"

Conflicts:
	.travis.yml
travis: run cppcheck with --exception-handling where it matters
travis: add -O3 -march=native -mtune=native to default CXXFLAGS
ValueFlow: Improved valueFlowForward. RHS in assignment.
Merge pull request #342 from matthiaskrgr/travis_working

Travis working
htmlreport: Use source_encoding to open XML files
avr.cfg: Added more defines.
avr.cfg: Added accidently commented out define.
avr.cfg: Added macros of stdint.h.
avr.cfg: Removed NAN definition.
travis: replace kernel check with clang check.

Check clang instead of kernel, which is a lot faster.
Make clang check failure fatal to the build.
travis: add -DCHECK_INTERNAL to the VERIFY=1 job to automatically fetch issues like #5869 via travis, check clang with --exception-handling