Fix solarized cursor in 24-bit Vim with light bg
Add `:Bright` command for lighter background

- sets bg=light
- sets color scheme to solarized
Fix output spacing for multiple batteries
Add XMonad bindings for "real" keys

New laptop receives "better" keysyms for:
- <kbd>F5</kbd> => <kbd>BrightnessDown</kbd>
- <kbd>F6</kbd> => <kbd>BrightnessUp</kbd>
- <kbd>Win</kbd>+<kbd>T</kbd> => <kbd>ToggleMonitors</kbd>
Map <kbd>VolumeDown</kbd> to volume control

- <kbd>AudioMute</kbd> on new laptop is a hardware mute button
Fix inherited Verman versions
Add `db-url.go` DATABASE_URL tool

- convert `config/database.yml` to `DATABASE_URL` or vice versa
- allows specifying the database name as an argument (first use case)
Use `db-url` in `with-fresh-test-db`

- `database_url` gem changed its API, so I wrote `db-url` tool in Go