fix interface inference for "extern inline" functions
splitting tests, adding (failing) test for parameter function
fix marking of parameters and inference of functions with regard to parameters

previously function pointers in parameters could be mistaken for function names
updated tests
updated bdd defaults
update FeatureModelFactory interface

 * allow user-defined variable-name prefix instead of hard-coded CONFIG_
 * better error message on failed assert
improve FeatureExprParser

* supports now also atMostOne
* oneOf is implemented more efficiently
* allows to parameterize how to recognize feature names
* supports prefixes for feature names
workaround for Scala-Java interaction with default parameters
remove unnecessary file
remove compiler warning
untrack .idea files
proper checking of __builtin_va_...

support for __builtin_va_args type and checking types for BuiltinVaArgs function
add support for weak exports

(and generally flags, although no other flags are used yet)
add additional error subproject for generic error reporting infrastructure
first attempt at checking for integer overflows

pointer arithmetic / array access only
checking for integer overflows in function parameters for security relevant functions

functions are hardcoded, currently malloc, realloc, and calloc only
better error reporting with location information

for rewritten expressions (arrays and unary expressions)
reduce false positives

previously any assignments created a security context
warnings about integer narrowing
ignore SecurityWarnings in existing test cases

causes many false positives (or just warnings, not errors) that we do not care about here