* Also catch preprocessor errors possibly issued during loading files
Currently only errors that are issued during preprocessing are caught.
* Bump simplecpp, implement suggestions
Use return value checking instead of catching an exception for calling
Preprocessor::loadFiles().
Handle new enum value simplecpp::Output::EXPLICIT_INCLUDE_NOT_FOUND
where the corresponding enum is used in Cppcheck.
* Use "noloc" location if an explicit include can not be opened