Added five.six function to return 6
Added negative, loud, and smooth functions

First two are self-explanatory. five.smooth will "smooth out" the harsh edges of 5.
Added examples for new functions
Merge remote-tracking branch 'upstream/master'
Added tests for negative, loud, and smooth
Update test.js

Wasn't paying attention...
Merge pull request #61 from Gsinti/master

Removed five.six, added negative, loud, and smooth