zsh: Add useful aliases for `ls`
zsh: Add useful aliases for `ls`

By default the output of `ls` is not coloured, even though coloured
output is very useful. For example, it makes it much easier to
distinguish between files and folders.

Furthermore, I often want to see all files (including the ones that are
hidden), which is realized by the `la` alias. The `l` alias is useful
for viewing only non-hidden files, and the `ldots` alias can be used to
only view hidden files.

PigeonF/.dotfiles