FYI: changes backed out

[Holly Cummins <ho...@googlemail.com>]

Hi all,

I've backed out some concurrency changes that were made in the  
blueprint namespace handler registry last Monday, since they seem to  
be responsible for at least some of the test failures we're seeing in  
the builds, and it's been a week without much activity on a fix.

If the initial changes need to go back in, the application component  
tests should be run before committing any revised fix.

Holly