fix syntax

This is a follow up to #124.

This changes the behaviour as follows: ```\lstinline``` behaves like ```\verb``` and ```\lstinputlisting``` behaves as any other file input would. I think this makes much more sense and also the ```lstinputlisting``` was broken if any macro was used within the argument of it, like ```\lstinputlisting{\MyPath/foo.bar}```. Which would result in "verbatim" syntax until the next normal latex-macro.

Edit: Fixed typos.