01/01/2019 Released V1.0 of libmemoize

05/01/2019 V1.1: cleaned up the code a bit, added option to free

	pointers that are allocated in the process of building the cache
	with the free_results_pointers option. This allows the cache
	generation function to, say, allocate strings which can then be
	freed later.

14/08/2019 V1.3: fixed bug when compiling with clang caused because
	part of the header file was hidden in __MEMOIZE__  when it should
	not have been.


29/08/2019 V1.4: added consts to struct pointers where appropriate, and Pure
	functions for gcc-9
