v0.1.2

New features:
- ask before quit if scanning for changes has taken a while
  commit 2046d857859c1e7b6f26069ac30e4ffcda42424e
  commit a01fa5548f41ef12fd22f1b67f1abe2cffad7573
- HelpItem: support several commands
  commit b50600b0bc7d99bd8acace9f95727b9276d26d39
- added help items to directory chooser
  commit f78cc40cbeeaa6a7d39ca6ce3152cf3102ae0164

Bugfixes of the program:
- don't crash if help bar is empty
  commit 5a9bef40cb41f0c26ab574a2bd6ae560c9621045
- correct processing of markup
  commit d16ee64a3661bd2ee7d5eaf473d23a4dac0218f1
- help bar of progress bar is configurable
  commit 21ab24feea1771357ac7eecc916b5cb8d031343a
- multi key support for dialog and help
  commit 1eb1dbcadb3c673af33255c3d64cbe793f3c76db
- always update help bar when switching to another widget
  commit c14db4837fb5ba439dd0e1a558e3a4219eb89cb7

Bugfixes of the package:
- mypy recognizes typing
  commit ff68e90fa3c17896e58d8310da5d84cc972fe552
- tox is checking tests with mypy
  commit a81e9b5d2fb0ad00c9da687866ddc5d0cf2be6c3
- run tox without internet
  commit c99cbe3c42e6b5614b8c955327493c24f92ced69
- added forgotten asserts
  commit 48fc0c16143adc8e04d56d7821b2287788fbe72d

Notes:
- synchronization logic is implemented but UI is still missing
  commit 3be2844deae9b71d2275a74637e5017e75be9622