updated strings

git-svn-id: https://plugins.svn.wordpress.org/loco-translate/branches/dev@815587 b8457f37-d9ea-0310-8a92-e5e31aec5664
added relative paths to Poedit headers and cache flusher

git-svn-id: https://plugins.svn.wordpress.org/loco-translate/branches/dev@815588 b8457f37-d9ea-0310-8a92-e5e31aec5664