Fixes #7: Strip slashes from tweet text, version bump to 0.7.13.

git-svn-id: https://plugins.svn.wordpress.org/tumblr-crosspostr/trunk@903737 b8457f37-d9ea-0310-8a92-e5e31aec5664
Oops, update readme to add correct info for WordPress Plugin Repository.

git-svn-id: https://plugins.svn.wordpress.org/tumblr-crosspostr/trunk@903739 b8457f37-d9ea-0310-8a92-e5e31aec5664