Tidied up SSE code. Added AVX support. Compiles, but execution untested
(current CPU doesn't support AVX, gives "Illegal instruction" error).
Compile fixes for Mac OS X under gcc 4.2.
Fixes for compilation on Mac OS X, with clang++ compiler now favoured
(has AVX but no OpenMP support, whereas g++-4.2 has OpenMP but no AVX
support...). AVX seems to be working, required some fixes to ensure
memory allocations are correctly aligned for 256-bit SIMD vectors.
Further work on SSE and AVX support. Removed non-default constructors
from avx_float, avx_double, sse_float and sse_double types, which gives
~10% performance improvement when simulating PZ model.
Updated compiler preferences for Mac OS X. Fixed compile warning in
Schedule.hpp.