Support for removing old classes, updated defaults, refactor

The plugin is now called using .eq() instead of .breakpoint()

Functionality has been added to allow the plugin to cleanup after
itself by removing old class names which match a prefixed pattern

Default options are now exposed publicly allowing them to be
modified, a prefix attribute has also been added to allow
specifiying a custom value
Basic resizable demo

Added a basic demo showing the plugin working in conjunction with
jQuery-ui .resizable attached to the stop callback