Adding 'copy' action to the resource template browser.

[fukuchi]

This patch allows the user to copy an existing resource template.

Use case: Imagine you have some resource templates and now are going to create a new one. Typically your templates may share some properties - 'author', 'containedIn', 'dateCreated', etc, etc. Some of them may be private and/or mandatory. Creating a new template from scratch is annoying and often causes human errors. Export-and-Import could solve the problem, but not smart.

How to use it: You'll see copy icons beside edit icons in the resource template list as following:

Click the icon and you'll be directed to the form of the new template that is copied from the original template.

Note: This patch does not provide any API for copying action. IMHO, in the case of API-based operation, GET-and-POST is enough for typical use cases.