Travis: Automatically test KS submissions

With @sircmpwn's permission, this should download and test any mod from
KerbalStuff. This is only triggered on PRs, and will automatically fetch
the latest stable netkan.exe for testing.
Travis/KerbalStuff: Test against the branch we're merging into.
Netkan/KS errors are more verbosely reported.
Travis: Also test github releases.
Skip inflate tests if no .netkan files have changed.
travis: Really mark test as skipped if no .netkan files changed.
Added Regolith for 0.90

Karbonite now requires this rather than ORSX.

@BobPalmer's other mods may also depend on Regolith where they
previously used ORSX, but since it's past 4am localtime I'll leave them
to one of our more wakeful indexers. :)

Also many thanks to @DuoDex, who atually did most of the work here in
Merge pull request #188 from pjf/regolith

Added Regolith for 0.90
Adds author to Regolith
Update AdvancedFlyByWire for version 1.4
Merge pull request #187 from Ippo343/master

DangIt recommends Entropy again
Adding EnhancedNavball
Rename EnhancedNavball.netkan to EnhancedNavBall.netkan
Change DeadlyReentry version to 0.90
Updated version, Added Repo.
Merge pull request #192 from playful1510/patch-1

Updated version, Added Repo.
Updated RCSLandAid.netkan
Added ksp_version, homepage
0.90
Merge pull request #196 from playful1510/patch-1

Added ksp_version, homepage