constants: remove init/destroyROM functions
threading: use 32bit atomic integer operations exclusively

The 32bit operations have better portability and have less onerous alignment
restrictions.
wavefront: fix msvc warning

warning C4800: 'unsigned long' : forcing value to bool 'true' or 'false' (performance warning)
threadind: fixes for VC11 Win32 includes, prune two unused functions
fseeko for mingw32
refactorizaton of the transform/quant path.

This patch involves scaling down the DCT/IDCT coefficients from int32_t to
int16_t as they can be accommodated on int16_t without any introduction of
encode error, this allows us to clean up lots of DCT/IDCT intermediate
buffers, optimize enode efficiency for different cli options including noise
reduction by reducing data movement operations, accommodating more number of
coefficients in a single register for SIMD operations. This patch include all
necessary changes for the transfor/quant path including unit test code.
dct: fix gcc warnings
primitives: clarify constness
disable denoiseDct asm code until fixed for Mac OS
replace char to int8_t, where it should be signed char
fix for rd=0
encoder: fix analysis file read
luma_hpp[4x4]: AVX2 asm code bug fix