Mavericks fixes

This release fixes two issues encountered in Mavericks.

1. The 10.9 SDK no longer supports directly linking to vecLib; instead, it seems we must go through the Accelerate framework instead.
2. There is a bug in the Mavericks implementation of sgemv when the input data is not aligned on 8-byte boundaries (yes, 8, not 4). I've added code to address this issue by intercepting sgemv calls, and translating them to equivalent sgemm calls. The translation occurs only if the alignment would exercise the bug; otherwise, the data is passed directly to sgemv.

The code has also been refactored to increase reuse of the custom BLAS replacements.