Only show one "Copy" button and then a modal on "Copy pages and collections"

[Steven]

TITLE: Copy page or collection Front end display issue

BUG SUMMARY:
When a user has created pages and collections and wants to create a copy of a page, the copy page or collection page displays the copy page and copy collection buttons on two lines
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Environment tested: Master
Browser tested: Chrome

PRECONDITIONS:
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1) Mahara user exists (no roles)
2) User portfolio page exists
3) User collection exists

TEST STEPS:
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1) Log in as Mahara user
2) Browse to the Pages and collections overview page
3) click the "Copy" link/button

Expected Result: Previously created pages are displayed. ✔ Buttons used to copy Collections or pages are displayed on one line

Actual Result: Previously created pages are displayed. ✔ Copy collections and copy pages buttons are displayed on 2 lines ✘ - see attached screenshot

[Robert Lyon (robertl-9)]

The text on the buttons are too long - would be better to change this to work like 'Add page' button with modal popup

[Rebecca Blundell (rjb-dev)]

The listing of pages and collections stays and each entry gets a copy button, which brings up a modal allowing you to select page or collection.

If a page is not in a collection, click the copy button without the modal, as no selection between collection and page is required.

This functionality does not touch preview of collections and pages. It's only the button.