Correctly handle Erlang comments

[bipthelin]

Erlangers tend to use multi-comment-starters to denote different types of comments, i.e. inline-, function- or header-comments. e.g:

%%% @doc Hi!
-module(hi).

%%@doc Function x
function x() -> y.

This commit supports one or many %

[rottmann]

Thanks, hope to find some time this week and implement it (and all the other pull requests).

[rottmann]

Thanks, changed in the coming version 0.8.0