Implement better arrows for modal pager

Controls (left arrow, right arrow and close button) are always visible. Show the left/right arrows will demonstrate that there is more content, without necessarily needing to hover over the content
Controls are at 60% opacity by default. On Hover this increases to 100%. Feel free to use any animation which may enhance things.
The position of the arrows have been moved.
Pressing escape on the keyboard should close the modal also.

Let me know if you've any questions at all.