These are two small quality of life changes I've made to my local Concrete5 fork

These changes deal with better support for the adodb mysqli driver and a small fix to the user selector helper to make it clearable (like the page selector and image selector) and to fix a javascript scoping bug.  Both changes have details attached to them, although this is my first pull request so I apologize if it's done incorrectly.

My concrete5.org handle is NazWeb.