Log Message:
Update net/youtube-dl to 20160501.

Changes:
2016.05.01
[xminus] Fix extraction (closes #9228)
[douyutv] Improve extraction and update tests
[openload] Fix title extraction and misc improvements (Closes #9298)
[muzu] Remove extractor (shut down in October 2015)
[normalboots] Fix extraction
[malemotion] Remove the extractor (MaleMotion is closed) (Closes #9311)
[nuvid] Fix extraction
[sexykarma] Rename to WatchIndianPornIE and fix extraction
[wsj] improve extraction
[ccc] improve extraction
[*] Misc fixes and improvements

2016.04.24
[people] Add extractor
[quickvid] Remove extractor (Closes #9258)
[tvigle] Fix extraction (Closes #9259)
[streetvoice] Fix extraction
[dispeak] Add new extractor
[mgtv] Add new extractor (closes #9212)
[dispeak] Several fixes
[planetaplay] Remove extractor (Closes #9256)
[dump] Remove extractor
[tubitv] fix extraction (closes #8741)
[nbc] add support for today.com (closes #2909)
[nhl] Add new extractor (closes #8419, #8798)
[dplay] Various improvements and fixes
[yahoo] Extend _VALID_URL and fix extraction
[yahoo] Extract all <iframe>s
[*] Misc fixes and improvements

2016.04.19
[mixcloud] Added support for user uploads, playlists, favorites and listens
[generic] Add support for LiveLeak embeds
[karrierevideos] Fix extraction
[lecture2go] Fix extraction
[arte:info] Add extractor (Closes #9182)
[ministrygrid] Fix extraction and modernize
[ubu] Remove extractor (videos on ubu.com are now hosted on Vimeo)
[wayofthemaster] Remove extractor (now using YouTube embeds)
[mixcloud:stream] Add new extractor
[karaoketv] Fix extraction
[mooshare] Remove extractor
[instagram] Add support for embed URLs
[instagram] Add support for iframe embeds
[extractor/generic] Improve instagram embeds (Closes #9213)
[nerdist] Remove extractor (now uses brightcove)
[*] Misc fixes and improvements