Fixed bug where glance image cache stall timeout set in the glance
add/edit form does not take effect due to incorrect attribute being used.

See also image_cache_stall_timeout in:
        bc-template-glance.json
        _edit_attributes.html.haml
Removed unused pid_directory attribute.
Use sql_idle_timeout that's configured in the GUI instead of hard coding.
Merge pull request #160 from cdearborn/pull-req-release-hydrogen-master-45a4e447daec54f3fef22397178074a3fe860fa3

Fix for 2 bugs where attribs configured thru GUI were ignored, removed unused pid_directory attrib [1/1]