Merge branch 'release/1.1.0' into develop

Version 1.1.0

Fixed:

Issue #8: Error message after install: "TodoTxtMac" is damaged and can't be opened. You should move it to the Trash. Note: Application is no longer sandboxed. Sandboxing requires the code to be signed by a valid Apple Mac Developer ID.

Addressed:

Issue #5: Help isn't available for TodoTxtMac. Added a link to the web site to the Help menu. A Help Book will be added to the application in the future, which will fully close Issue #5.
Implemented "Set Priority" method (keyboard shortcut Y). Closes Issue #9.
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'

Version 1.1.1

Added:

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