Filesystem littered with directories named '~'

[TheLonelyGhost]

Apparently ~ does not mean the same thing as $HOME at all points in the ZSH configuration.

Expectation:

• zsh completion stores cache in dotfile in home directory

Actual result:

• zsh creates directory called ~ in current working directory where command was executed, then creates associated dotfiles for cache

[benohara]

Merged your PR to fix this.