Skip blank lines and comment lines

[CiaranOMara]

This PR:

• adds references to the BEDv1 specification to the documentation.
• adds comment and blank lines to the state machine.

Closes #13.

[edmundmiller]

New to Julia question, why does it think those pieces of code aren't covered?

[CiaranOMara]

@emiller88, for that particular new code, it probably doesn't get hit because it's in an anonymous function that immediately returns its result. So, it's never called except when the state machines are made.

[edmundmiller]

In that case, this looks good to me! Not sure if my review has any weight, but just trying to get involved!