Don't display footer on metadata & changes page

Fixes the accidental display of the footer on the metadata and
changes page.

COUCHDB-2502
Merge commit 'a762e7cae4902b34fb3fbf8f2c8c0c7449798cea'
Split out couch_httpd

This is the first of many steps to correct the application dependency
tree.
Move couch_js_functions.hrl to the include dir

This should probably be ditched for proper priv resource files. This
move simply allows couch_httpd to find the header for oauth purposes.
Add couch_httpd to reltool.config