More formats for pandoc

[denismaier]

With bibtex you can use many different commands, \cite, \footnote, \textcite, etc. But for pandoc only the basic pattern is currently supported. Would it be possible to add additional options:

• plain: @doe (=not in brackets)
• no author => [-@doe]
• narrative citation / in-text => @doe [12]

(Plain and no-author could probably also be combined.)

[tmalsburg]

Totally possible but I'm not using pandoc / markdown myself and don't have time to work on this. If you'd like to create a PR, I'd be happy to provide you with feedback and suggestions.