[Standards] XEP-0317: Hats, Update and complete the protocol

A few weeks ago I made an important pull request to complete, fix and update the XEP-0317: Hats. https://github.com/xsf/xeps/pull/1437 This PR included the following changes: * Specify a urn:xmpp:hats:commands:dcreate command to add a hat to the available list * Specify a urn:xmpp:hats:commands:ddestroy command to destroy a hat from the list * Clarify how the service should broadcast the hat changes when it is edited, assigned, removed or destroyed * Specify a way for an entity to get the complete list of hats using a hash in disco#info * Add a hue optional parameter allowing entities to assign a color to the hat that can be displayed properly in any conditions on the client (as explained in XEP-0392: Consistent Color Generation) * Standardize all the form fields using XEP-0068 * Fix some typos I tried to reach the authors without success so I'm trying again using the mailing list. I'd really like to move it forward then we can start implementing them in our clients and servers. Regards, edhelas