Make sure string is lowercase from UI

Author Scott Yeskie <scott@yeskie.com>
Author date 2016-07-21 00:09:36
Author local date 2016-07-20 17:09:36 -0700
Committer Scott Yeskie <scott@yeskie.com>
Committer date 2016-07-21 00:09:36
Committer local date 2016-07-20 17:09:36 -0700
Commit 85185caaac537e50a7180f25b1b44f82a7c6e80b
Tree 292cc245e118c1411ead733602eaf6ff94796723
Parent e3f0bd1c19d875af8f3efae446777097d5e9e3e7
Make sure string is lowercase from UI

All chat messages are converted to lowercase before being checked.
From the UI, it didn't convert the configuration string, so if the user
entered an uppercase string, the addon wouldn't work.