Get OA_HEADERS using the accessor function
Introduce a function to extract a header from OA_HEADER
Rewrite http_Merge() to pull from OA_HEADERS
Quote etags used in tests.

Though unquoted Etags are commonly seen in the wild, according to rfc2616
the entity-tag itself should be quoted.
Pass a dstat arg to oc->updatemeta()
Complete obj->objcore change for bans
Update the XHTML in the default guru page.

Submitted by:	mattrobenolt
Approved by:	mithradir