Add FTB Modpack Support

[joshuacherry]

• Create a minecraft_server option for FTB
• Download Modpack
• Unarchive Modpack
• Set executable name (tasks/setup/main.yml)
• Update test suite
• ???
• Profit!

Test suite will test the following 4 FTB modpacks since these are the top 4 by download as of today:

ModPack	Pack Version	MC Version	Download URL
FTB Presents SkyFactory 3	3.0.8	1.10.2	FTBPresentsSkyfactory3Server_3.0.8.zip
FTB Presents Direwolf20 1.10	1.9.1	1.10.2	FTBPresentsDirewolf20110Server_1.9.1.zip
FTB Beyond	1.5.3	1.10.2	FTBBeyondServer_1.5.3.zip
FTB Presents HermitPack	1.7.0	1.10.2	FTBPresentsHermitPackServer_1.6.1.zip

[benwebber]

I've never used FTB so I'm a bit confused by how it works. Is FTB a modded server that allows administrators to install mods? Or is each modpack a server distribution?

[joshuacherry]

FTB is more like a "standard" of modpack distribution built on forge. Each pack I specified above is a different server distribution of mods, sometimes upwards of 80+ mods that the modpack creator has put together and addressed mod conflicts.

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