Fix initial dimensions when launching in fullscreen.
Fall back if luafilesystem isn't present.
Fullscreen tweaks.
Don't make the canvas too big.
Don't allow fractional scale when using set-wh.
Allow creating new files that don't already exist.
Allow setting fixed dimensions.
Fix scrolling offset.
Add describe command.
Don't let the minibuffer get fuzzy for fractional heights.
Docstrings for all fennel-implemented commands.
Move completer to editor prop.
Consolidate all editor state into state module.
More consistency around window splits.

There's always a list of windows, instead of only being splits when
the windows are split in more than one.
Echo errors to minibuffer.
Add notion of current window as distinct data.

Previously it was inferred from current buffer, which caused bugs when
the current buffer was visible in two windows at once.
Add bogus shell mode that doesn't really work.

It could maybe be made to work with luaposix, but it's got really bad
documentation, and I really don't feel like deciphering it right now.
Factor common bindings for line-based modes into a common parent.