v1.6.0 Mod Packs

Description

The more professional Mod Pack release now that I have done some testing and noticed some bugs.
To use this feature:

1. click on the manage mods spanner icon of an install
2. at the top of your screen will be "import" or "export" mod pack buttons, click one

Additions

• Mod pack imports (JSON format)
• Mod pack exports (JSON format) with current installed versions of each mod
• Mod downgrading to specific versions (coloured orange in summary list)
• Progress bar for large mod packs
• Sort mods alphabetically in tables to make navigation easier
• Summary info box popup on recently installed / updated mods after successfully completing an update or import action

Fixes

• Broken youtube link to latest patch trailer is now the video thumbnail and an "open in user's browser" behaviour
• Installations squishing together PR:161
• Modpacks not obeying provided versions and just installing the lastest