fix multiline comment parsing to process some pathological case correctly
change functional macro apply order (same as appear order) because current implementation of state.apply does not handle functional macro which contains concatenatoion correctly.
modification for corresponding strange gcc behavior which can allow duplicate macro definition which has exactly same value.
implement more parsing expression in #if (==,!=,+,-,*,/)
skip parsing #if expression inside disabled block
implement parsing #if expression
support C-style integer type specifier L, U, LL, UL
support C-style integer literal 0x, 0b, 0%d+(octet)
add support for tenary operator
add support for #include_next
fix numerical literal parsing
small fix for parsing rare case in C system headers