Added anchor and image markdown snippets.
Added some spellings.
Moved FT specific stuff to their own folders.

So now I'm using ftdetect and ftplugin. One maps file types and the
other configures things on a per-filetype basis.
Removed the dedicated tpope section of bundles.

All mixed in now. Everything is sorted by category, not author.
Set the format options in markdown.

Fixes the comment tweaks that tpope/vim-mardown brings in. They were not
being applied without the correct formatting string for some reason. So
now lists and quotes carry down lines correctly.