NF - added signal-to-noise function to stats
Changed function name of SNR to signal_to_noise
changed function name and cleaned up some grammar
added gain parameter and made suggested changes to documentation
removed gain and fixed some errors
Added gain and updated documentation
added simple test for snr function
added more tests for snr function
added Msun alias for solar mass unit
Use RandomState in iterative tests
remove a commented line
Add mass-energy conversion.
Add some unit tests for the mass energy equivalence.
Handle numpy < 1.8 bug getting row from masked table with object cols
Merge pull request #1229 from taldcroft/table/fix-masked-row

Table row access failure with masked tables
Simplify the use of wheels for Travis following @Cadair's method
Fix syntax error
setuptools needs to be upgraded
Use inequality for Cython version since wheelhouse has 0.19.1 and we don't mind exactly what version is used as long as it's recent, and fix syntax error for SciPy.
Tidied up comments in .travis.yml