Always checking num_cpu_avail() regardless of whether threading will actually
be used adds noticeable overhead for small matrices. Most other uses of
num_cpu_avail() do so only if threading will be used, so do the same here.
Modify complex CBLAS functions to take void pointers instead of float or double arguments (to bring the prototypes in line with netlib and other implementations' cblas.h)
Craig Donner
Martin Kroeker
Werner Saar
Timothy Gu
Xianyi Zhang