Inline code and code block snippets - Create pandoc.snippets

Hi there!

I added to new snippets to the `markdown.snippets` to be able to write faster inline or block code:

*     `snippet ilc "Inline Code"`
*     `snippet cbl "Codeblock" b

I also created a `pandoc.snippets` files for those who are using the Pandoc Flavor of Markdown. Basically it is just a copy of the `markdown.snippets` file.

Hope this can help! :)