Update LLFloaterSettingsDebug to match up with v-d.

Adds boost::bind and makes the floater a singleton.
Zi Ree's Debug Setting Floater awesomeness (Search!!)

Made to work with Singularity, and also be a bit better..
Alphabetizes includes.
Switches settings combobox to a scrolllist, and Boolean combobox to a radiogroup.
Makes floater resizable, aligns a lot of the UI, and prepares it all for proper resize behavior.
Adds Copy button for copying the name of the debug setting.
Yay, verbosity! Also adds FloaterDebugSettingsRect to keep track of the floater's size.

Also somehow the getInstance line snuck out of last commit... tossed it in here.
Feature request: Alt-R for Region/Estate floater