updating flixel imports to use 'org.' prefix

While working with the Tiled demo, I was getting a lot of "class not found errors" because the imports for flixel packages were missing the "org."

Unsure if this is because of a recent restructuring of the lib, or project-specific search path configuration, but I think having the full path in there should mean this code will be more portable.

Sorry about the boat-load of whitespace changes. My editor was configured to strip trailing whitespace on save (and I didn't think to disable that feature).