Prompt to install previous versions after a game update

[legoandmars]

Some users have communicated displeasures with having to track down and re-select all of their mods after a game update, and this feature should fix that in a way that the current Save Selected Mods option can't.

• Specifically tells you which of the user's mods aren't updated yet
• Gives the user a choice of whether or not to select old mod
• Works with mods not installed through Mod Assistant as long as they're on BeatMods

I'd like to look into a few more things before merging this, though:

• Basic feature
• Localization support
• Option to disable the feature
• A more descriptive message when not all of the user's mods are updated
• Look into viability of a "Not Updated" section directly in the mod list to give a visual indicator that MA isn't broken, the mods just aren't updated
• Switch SemVer to use Hive.Versioning and AlmostVersion to properly support weird game versions like "1.3.0p1"