Break up dotfiles

[evangoad]

Vim

*.vim files in the directory ~/.vim/plugin will be loaded since vimrc contains plugin on

Tmux

According to tmux documentation, source-file can be used on a glob(3) pattern. Theoretically I could add a source-file ~/.tmux/custom-dir/* and load many files at once.

Zsh

this looks pretty good.

[evangoad]

Since the introduction of #67, I no long have a clean way of breaking up the vim plugin install commands. I got a considerable speed boost from using strand, so I likely won't be going down this path any time soon.