Fixed crash in CheckVaarg::va_start_argument (#6032)
Fixed crash if va_start is passed less arguments than expected
Changed handling of unhandled characters:
- Don't abort checking (reverts 42140b64888c7f313f6c9593447647c97de3bfa4)
- Modified error message: New Id unhandledCharacter, removed redundant line information, improved message text
Refactorizations optimizing std::string usage.
Refactorization: Moved condition in Token::tokAt() out of loop.
Keep console open in testrunner
Use C++11 std::sto* instead of std::ato* where appropriate (emulated in cxx11emu.h)
Added AST validation