Improve keybinding descriptions

This adds a bunch of tooltips to keybindings and updates some keybinding descriptions (i.e. labels).

It's in preparation for displaying more keybindings on-screen (in the bottom right of the screen),
and so due in part to laziness it shortens some descriptions so that we don't need to manage both
a short and long description (for on-screen vs in-menu). Nonetheless I've added a ShortDescription
field for when we do want to have both a short and long description.

You'll notice that some keybindings I deemed unworthy of the options view have longer descriptions,
because I could get away with it.

pkg/gui/controllers/status_controller.go

@@ -36,11 +36,13 @@ func (self *StatusController) GetKeybindings(opts types.KeybindingsOpts) []*type
 			Key:         opts.GetKey(opts.Config.Universal.OpenFile),
 			Handler:     self.openConfig,
 			Description: self.c.Tr.OpenConfig,
+			Tooltip:     self.c.Tr.OpenFileTooltip,
 		},
 		{
 			Key:         opts.GetKey(opts.Config.Universal.Edit),
 			Handler:     self.editConfig,
 			Description: self.c.Tr.EditConfig,
+			Tooltip:     self.c.Tr.EditFileTooltip,
 		},
 		{
 			Key:         opts.GetKey(opts.Config.Status.CheckForUpdate),