update trunk to 0.4.0

git-svn-id: https://plugins.svn.wordpress.org/wp-bootstrap-carousel/trunk@1021031 b8457f37-d9ea-0310-8a92-e5e31aec5664
add pot file

git-svn-id: https://plugins.svn.wordpress.org/wp-bootstrap-carousel/trunk@1021033 b8457f37-d9ea-0310-8a92-e5e31aec5664