Wp-calypso: Editor: Copy UI is inconsistent across post types.

[kwight]

While users can copy both posts and pages, the functionality is called "Duplicate" for posts, and "Copy" for pages.

Also, with the addition of Jetpack's Copy Post for adding this functionality to Calypsoified Atomic and Jetpack sites, the current ?copy parameter should be updated to the prefixed ?jetpack-copy.

[gwwar]

I noticed that too earlier, maybe stick with "Copy".