Support for persisting state between launches and relaunch by shortcut!
- Persist some layout state between launches. #945, #948, #151
- Add shortcut for relaunching. Thanks, @skast96! #910, #361, #956
- Fix a bug with tall-right incorrectly positioning windows when multiple screens are in use. #955, #933
- Fix a bug that would lose track of windows that have exited fullscreen. #954, #674