Merge pull request #48 from nilsbore/libav_subtree

[catkinized_libav] Changed libav to be subtree instead of submodule
Update package.xml
updated changelogs
0.0.1
Update README.md
Merge pull request #49 from nilsbore/patch-1

Update README.md
Merge remote-tracking branch 'upstream/hydro-devel' into libav_subtree