Added AgaviContext::createInstanceFor(), closes #780
reverting bad commit in 974d6785aeea4828a1fcc9a390a50907f4f59f99, refs #780
Added AgaviContext::createInstanceFor(), closes #780, this is a proper version of the faulty commit in 974d6785aeea4828a1fcc9a390a50907f4f59f99
Merged revisions 2888-2889,2891 via svnmerge from 
http://svn.agavi.org/branches/1.0