Enabled compilers' (GCC/NVCC) fast-math flags.
Corrected function's definitions. Math Optimizations.

Notes:
* CEC 2013 F.9 (Weierstrass) code definition, appears to be incorrect.
* Switched from calls to pow(x, 0.5) to sqrt(x).
Merge pull request #3 from rdelcueto/testing

Testing