Bug 1102538 - s/Ion/Jit/ where appropriate. r=jandem.

--HG--
rename : js/src/jit/IonAllocPolicy.h => js/src/jit/JitAllocPolicy.h
rename : js/src/jit/IonFrames-inl.h => js/src/jit/JitFrames-inl.h
rename : js/src/jit/IonFrames.cpp => js/src/jit/JitFrames.cpp
rename : js/src/jit/IonFrames.h => js/src/jit/JitFrames.h
rename : js/src/jit/IonLinker.h => js/src/jit/Linker.h
rename : js/src/jit/IonMacroAssembler.cpp => js/src/jit/MacroAssembler.cpp
rename : js/src/jit/IonMacroAssembler.h => js/src/jit/MacroAssembler.h
extra : rebase_source : 60604d525312a7ef7b2eb92617c7a4e801fb2d81