vifm is removed in favour of nnn, with the keybindings in nvim being
changed. TODO: improve the colorscheme of `nnn` to match `ls`.
All nvim plugins that were responsible for language syntax highlighting
are removed in favour of treesitter[1], a syntax highlighter that parses
AST instead of being regex-based. This is still experimental, but my
tests so far have not encountered any issues.
1) https://github.com/nvim-treesitter/nvim-treesitter
The swayidle command in the service was straight up broken, this commit
fixes that.
Environment Variables set in the `session-variables` file are now
correctly imported across the system. This fixes `EDITOR` defaulting to
`nano`.