aliases: Add `apt-update-repo` to update a single PPA
vim: Remove unused color schemes
zsh: Remove the autosuggestions plugin

It was causing loads of extra zsh processes for the completion server
whenever something ran a login shell.
vim: Move 'syntax on' to a later point to pick up bundles ftplugins
vim: Remove obsolete scss plugin, there's a better one
bin: Remove unused executables

adb: Just install the SDK, this doesn't work everywhere
setup-ruby: `brew install rbenv` suffices
_tmux_focus_task: Don't use TaskWarrior anymore
shell: Don't set window titles
vim: Use the json plugin for syntax highlighting instead of js