Support named parameters

Use introspection to convert named parameters, as in
``np.ones(5, dtype=int)`` into regular ones.
Re-enable doctest for analyses/transformations/optimizations

doctest is not recursive...
Allow call to ``complex`` without parameters

complex() -> 0j
Merge pull request #270 from serge-sans-paille/named-parameters

Support Named parameters
Fix a corner case of isclose usage

nt2 does not handle bool parameters for is_nan or isfinite...
Merge pull request #282 from serge-sans-paille/fix-isclose

Fix a corner case of isclose usage
Check mode arguments for benchmarks
Add randomness in benchmarks execution order
Change default compiler flags for benchmarks