[extractor/common] Add description to playlist_result
[prosiebensat1] Improve and simplify
Merge branch 'akretz-master'
Credit @akretz for prosiebensat1 playlist support (#4394)
Handle --get-url with merged formats (fixes #2883)

Outputs one URL per line
[nhl] Make sure we add '_sd' before the extension (fixes #4397)

'.replace' would find the first dot in the path.
[tvigle] Update test and modernize
[bliptv] Add support for audio-only files (Fixes #4404)
Merge branch 'master' of github.com:rg3/youtube-dl
Merge pull request #4395 from cryptonaut/issue2883

Handle --get-url with merged formats (fixes #2883)
[extractor/common] Document ie_key in url results
[extractor/common] Add generic SMIL formats extraction routine
[bet] Add extractor (Closes #4416)
Fix PEP8 issue E713
release 2014.12.10
[youtube] Handle missing DASH manifest (Fixes #4421, fixes #4420)
release 2014.12.10.1
[youtube] Pass in all variables to DASH manifest (Fixes #4424)
release 2014.12.10.2
[facebook] Make thumbnail and duration optional

Fixes #4425.
Looks like both properties aren't given to us anymore. For now, just fall back to not returning them.