Merge pull request #6 from tdesvenain/master

add a behaviour for IMicroblogContext local microblog support interface
reword IMicroblogContext behavior
fix testing thread cleanup
Simplify API to filter on either user or context, but not on both. Cleanup and restructure implementation.
Prepare plonesocial.microblog 0.4.2.
merge 0.4.x release and update changelog
Merge branch 'master' of github.com:cosent/plonesocial.microblog