Coverity build and upload target. Also GitFunctions.
.cmake files to reduce "code" duplicate
Merge remote-tracking branch 'origin/feature_dotcmake' into develop
Context menu tweaks

* Add create/copy instance actions to the context menu.
* Context menu for the instance view background.
* Top of the context menu is now a header, fixing the misclick problems.
Add Patreon button. Needs an icon (used I for now).
Give the Patreon button a logo
Merge pull request #211 from Drayshak/develop

Add Patreon button with logo
Remove specific OpenSSL version from BUILD.md
Let travis build a clang version
Merge pull request #212 from MultiMC/feature_travis_clang

Get Travis to build GCC and Clang versions on Linux as we consider moving to Clang on Linux in general
Detect and report missing local libraries.
Give more feedback for YggdrasilTask network errors.