Convert MathLib::toLongNumber() from template member function to toLongNumber() and toULongNumber() to avoid various problems compiling with Visual Studio
Fixed some coverity findings about dead code, fixed a misleading comment
Code cleanup of stack depth tracking. Replaced class with simple POD variable.
Use constant instead of magic number for AST recursion limit

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astyle formatting

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Implemented a slower but shorter version of MathLib::isNullValue() as suggested by PKeuS. Removed not needed test cases. Improved doxygen documentation for MathLib::IsNullValue().
AST: Fixed iscast detection in '*((DWORD*)&buf[0])'
Fixed #5682 (False positive: (style) Same expression on both sides of '&&')