added toolbar for image block options. Added functionality to change image size. Still needs the code to change image alignment.

git-svn-id: https://plugins.svn.wordpress.org/wp-content-blocks/trunk@784985 b8457f37-d9ea-0310-8a92-e5e31aec5664
updated code with image aligment feature for image block. Plus some minor css tweaks.

git-svn-id: https://plugins.svn.wordpress.org/wp-content-blocks/trunk@785586 b8457f37-d9ea-0310-8a92-e5e31aec5664