Updated the identification string documentation for the spin user function class.
Implemented the spin.renumber() user function.
Implemented the spin.rename() user function.
Implemented the spin.display() user function.
Reordered the user functions in prompt/molecule.py.
Implemented the spin.delete() user function.
Implemented the spin.create() user function.
Implemented the spin.copy() user function.
Removed a few unused imported functions.
A few comment fixes.