Further improvements in knc.h

- All vector data types now have the [] operator to ease the debugging
- The 'reduce_<smth>_i<num>' function names changed, as the code generator emits different names
- Several template function specializations were commented out to improve stability (at the cost of performance)

TODO:
Fix the code generator so it would emit 64 byte alignment for vector types (it doesn't do so even if --opt=force-aligned-memory is set) or knc memory intrinsics such as _mm512_load_epi32 will not work and load/store operations will work extremely slow