Added predictor stride argument(s) to subtract functions

Patch set 2: 64 bit build fix
Patch set 3: 64 bit crash fix

[Tero]
Patch set 4: Updated ARMv6 and NEON assembly.
             Added also minor NEON optimizations to subtract
             functions.

Patch set 5: x86 stride bug fix

Change-Id: I1fcca93e90c89b89ddc204e1c18f208682675c15
8 files changed