Some basic fixes to rd-rend2
Changed the extra refdef flags to match JA's stuff adequately.
ID_INLINE -> QINLINE
Add SDL stuff which is specific to rd-rend2
Lots of this {filtered} does not belong in tr_types.h, it isn't renderer-agnostic at all
Added MD4 file info to qfiles.h
ri. --> ri->
Use explicit casting for hunk allocations (which is now required in C++)