Rename inp to input_

This conforms to PEP8 style guidelines, which state:

> If a function argument's name clashes with a reserved keyword, it is
> generally better to append a single trailing underscore rather than
> use an abbreviation or spelling corruption. Thus class_ is better than
> clss.
Merge branch 'master' into input
Fixed a line that was too long
Merge pull request #80 from bartvm/input

Rename inp to input_