Bumped version to 1.1.1.

Changed keyboard shortcut for "set priority" command from `Y` to `I`. `I` is easier to reach on the keyboard, and `I` implies "importance" which is a synonym to priority.
Merge branch 'release/1.1.1' into develop

Version 1.1.1

Added:

Added "set priority" feature (keyboard shortcut `I`). Closes Issue #9.