[Development] Remember to rebuild qmake in dev

[Thiago Macieira]

Hello

moc.prf with MSVC now depends on a side feature in qmake to help support 
generating the moc_predefs.h file. If you're using MSVC, please remember to 
recompile qmake soon.

This does not affect GCC (any OS) or the Intel compiler (any OS), as both 
support the "dump macros" hidden feature. I have tested Clang but I did not 
test clang-cl.  

If clang-cl does not support compatibility with cl's -Bx argument, please edit 
moc.prf line 34 and submit a patch.
-- 
Thiago Macieira - thiago.macieira (AT) intel.com
  Software Architect - Intel Open Source Technology Center