Adds a prerelease option in update_settings to enable prerelease updates
Created by: idpaterson
This pull request adds a prerelease
option to the update_settings
dict which will allow users of my workflow to subscribe to a pre-release update channel. It was great to see that the version matching already handles version suffixes, so updating 0.6.0-alpha.1 to 0.6.0-alpha.2 worked as expected.
I did not add a note in the documentation about the Alfred-Workflow version at which the prerelease
option was added. The only backwards compatibility concern is if anyone ran update.py manually, since it now requires 5 rather than 4 arguments.