Add Encodable and Decodable for VecMap
Use FnvHashMap instead of HashMap in rustc
Add 'move' keyword to emacs, kate, and vim editor modes.
auto merge of #18821 : arielb1/rust/fnv-hash-map, r=eddyb

This should improve performance
auto merge of #18793 : swgillespie/rust/master, r=alexcrichton

I noticed today that `move` wasn't getting highlighted in my editor of choice (emacs), so I went ahead and added it as a keyword in the emacs, vim, and kate editor files. Apparently it has already been done for gedit.
auto merge of #18813 : csherratt/rust/add-encode-decode-vecmap, r=alexcrichton