Modify AutoUpdater behavior on macOS.

The AutoUpdater requires that macOS builds be code signed. That is currently not possible.
As a workaround, the autoupdater on mac will now alert users that an update is available and give the option to download the file directly from GitHub.
Closes dscalzi#16.

Fix native lib extraction for old MC versions.

dscalzi#18

v1.0.5-pre.1 - Investigating dmg auto-update issue.

v1.0.4 - Logic cleanup, minor bug fixes.

Removed the old workaround logic for queueing archives for extraction.
Removed the old forge callback (this was replaced a while ago).
Fixed a typo in _parseDistroModules (getType).
Use discordrpc straight from the repository. The author has refused to push the bugfix for nearly a month.
Fix timestamp issue on discord rich presence.
Dependency upgrades.

v1.0.3 - Moved from deprecated mojang endpoint, dep upgrade.