Adding SIMD support for all caches. Havent not yet tested SIMD cache_shared.v . Other: bug fixes in cache, mainly in nonblocking_fsm.v. Bug1: handle case when L2 stalls during writing back data to L2 from L1, Bug2: Handle case when we keep the cache stalled when a same line request matches in MSHR, in this case we need to stay in stalled state until our line is serviced from L2 and then only we service our request which blocked the cache.