Test: new copy and paste manual test.

This test makes it easy to test copy and paste both inside a Cappuccino app, and externally to and from other Cappuccino instances in other browser, or other applications, when using a text field or a collection view as the source/destination.
Fixed: copying from a CPTextField would not actually but the string value in the Cappuccino pasteboard.

Without this fix, when text was copied from a CPTextField, the value would be copied into the system clipboard (if possible), but not into the Cappuccino pasteboard. This meant that the text could not be pasted back in Cappuccino using e.g. Edit > Paste from the Cappuccino menu.

This fix ensures the appropriate text is copied both into Cappuccino's pasteboard and the system clipboard (when possible).