Migrate python-commands to vimscript commands

[DJMcMayhem]

Currently, commands are implemented in python. This is a big problem since python doesn't have full access to the state of vim when the command starts. The simple obvious solution is to replace all of the python commands with vimscript commands. That will allow the python code to be simplified, since we won't need to track things like mode, and count.

[DJMcMayhem]

This is currently in progress on a different repository: Vigor. Once Vigor supports all of the commands that V does, I will merge the two back together.

[vihanb]

why use separate repo and not branch

[DJMcMayhem]

¯\_(ツ)_/¯ 

[DJMcMayhem]

Everything is done! All logic, operators, motions, new commands, mappings, etc. are now implemented purely from within neovim! And beyond that, a ton of bugfixes, new operators and new features were added. I'm really happy about this particular milestone. Up next on the chopping block is better UTF-8 support, then after that maybe some more math.

[vihanb]

@DJMcMayhem +100 10/10 for less python :P

[DJMcMayhem]

It's not about removing python, it's about having it in a state where adding new features is actually remotely possible. I'm going to add more python down the road.