apply fix #3153 to openlibm also
do ARCH autodetection based upon compiler instead of host (fix #3153)
Add generalized eigenvalue decomposition
Merge pull request #3225 from JuliaLang/anj/geig

Add generalized eigenvalue decomposition
bitarray: performance enhancements (fix #2360)

Improve performance of convert to BitArray (and therefore
of bitpack) and of element-wise operations (e.g. `.<`, `.^` etc.)
bitarray: avoid some unnecessary bound checks
bitarray: rename assign_* to setindex_*

(only internal functions, so this is just cosmetic)
WINDOWS: fix memory bug introduced by #3078