Version log

	Version 0.1 List works

	Version 0.2 All Numpy types */
	Version 0.3 Change the module interface to allocate more nlp instances instead of one
	now use nlp = pyipopt.create(xxx)
		and nlp.solve
			nlp.close()

	you can create multiple instance of nlp. [Tested]

	Version 0.4
	
	To allocate more models in a hooker. Planning to move all the pointers to the 
	PyObject (callback function in Python) to the user_data field
	Therefore, the C callback function here can just dispatch it to the python
	callable object in the user_data [DONE]
	[We wrap the user_data twice]

	Version 0.5: Bug in H matrix fixed

	Version 0.5.1: some stupid spelling error in the source file and comments fixed

	Version 0.6: memleak fixed. (at least valgrind won't complain)

	Version 0.7: Fixed a bug for the value of m and n, a bug for reference counting.

