Revision 582020

[MRM-482] Saving a proxy connector after adding a new property results to HTTP 500 error
[MRM-477] Missing ability to manage proxy order.
[MRM-437] admin editing of proxy connectors fails in multiple instances
* Split giant ball of mud ConfigureProxyConnectorAction into seperate Add/Edit/Delete/Sort/List actions
* Added ability to maintain sort order.
* Added unit testing.
* Cleaned up Proxy Connector admin UI to allow for extra long Location / URL paths.
* Slideout Hide of the Advanced configuration options on the Proxy Connector list screen.