shape-outside: circle() reftests
added dom flag
fixed failure - changed radius to 40px
added EOF newlines
removed test case for shape margin extending beyond margin box. this is easier tested with a polygon so it'll be moved to that branch/pr
added EOF newlines to ref files (I missed them before)
Merge pull request #503 from rhauck/circle-reftests

shape-outside: circle() reftests