[generic] indicate when a direct video has been extracted

Fixes #4052.
[brightcove] Make _VALID_URL less greedy and check for empty URLs (#3541)
[generic/brightcove] Add a new test case for kijk.nl (#3541)
[wimp] Fix video URL regex
[played] Capture and output error message
[cnn] Modernize test definitions
[youtube] Skip sts if missing (Fixes #4095, fixes #4103)
[gamespot] Modernize
[heise] Fix description, thumbnail and format ID
[ustream] Use modern helper function instead of old HTML parser
[gamespot] Remove unused import
[utils] Remove unused get_meta_content function
[imdb] Simplify
[utils] Use a regexp instead of HTMLParser for get_element_by_attribute
[youtube] Clarify output
release 2014.11.04
[izlesene] Update test cases and modernize

The timestamp fluctuates with DST.
[channel9] Fix extraction
[cinemassacre] Keep both extraction approaches and make more robust (Closes #4109)
Merge pull request #4110 from nemunaire/channel9-fix

[channel9] Fix extraction