Update plugins to latest version.

Change-Id: I1c22bc0c83efec98d228a8ff28f7992f6b886eba
Moved filetype configuration to its correct place.

Trying to let Vim do the hard work for me. Anything that is used only by a
certain file type needs to be on its correct `ftplugin` directory.

Change-Id: I119ae331f0f20c5b83f4df2239f5c9f0966514a6