Prepare smartscan to be a package.el file that would be accepted into MELPA and others

Hello, Mickey.

I made some modifications that I think will move smartscan toward a state that would let it be accepted into package repositories. Please let me know what you think of it; I'm open to your feedback about it. 

Here is a summary of the changes and my reasoning for them:

* Prefix identifiers with smartscan -- since Emacs does not have a namespace function, the maintainers of package repositories recommend prefixing identifiers with a unique name to avoid collisions.

* Convert to global minor mode -- by making smartscan a global minor mode, it can have a keymap, which makes keybinding collisions more palatable.

Let me know what you think; I'm excited about this becoming a package that I can easily install and recommend to others.

Regards
Ryan Mulligan