libbpg 0.9 (new formula)

Closes #34722.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>
libbpg: add 0.9 bottle.
libbpg: use text_fixtures function.
youtube-dl 2014.12.06.1

Closes #34733.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>
youtube-dl: update 2014.12.06.1 bottle.
Mark private VCSDownloadStrategy methods
Make cache_tag private
Make __path methods private
Make repo_valid? private
Add repo_valid? to remaining VCS strategies
Add clone_repo to remaining VCS strategies
Extract update from fetch in VCS strategies
Remove method that duplicates superclass implementation
Move SVN URL munging to initialize
Use start_with? instead of a regexp
Move fetch implementation into VCS strategy superclass
Mark private SubversionDownloadStrategy methods