[Vim] Minor updates to <Leader> maps

Removed some unused ones, swapped a couple.
[Vim] Move editing functions to autoloads
[Emacs] Fix typo
[Emacs] Reparse exec-path for fish shell

Fish delimits PATH with spaces instead of colons.
[Emacs] Remove package deps from Cask file
[Emacs] Do not use absolute paths for executables
[Emacs] Reformat PATH inherited from fish

So that subshells spawned by Emacs can find things.
[Emacs] Theme some of Magit mode