Update README.md
Added CONTRIBUTING file
Removed travis file
Cancel YTS when a new one is started

Fixes popcorn-team/popcorn-app#397 and popcorn-team/popcorn-app#347
Displays special characters correctly, fixes #291, #425
Moved YTS request abort into fetch
Update sidebar only if visiable
Update CONTRIBUTING.md
Update README.md
Merge pull request #467 from Multy7/master

Update CONTRIBUTING.md to point  to the UserVoice portal for feature suggestions