added memcmp func
added memcmp func

added int memcmp(void const* block1, void const* block2, size_t number);

Compares first number bytes in two memory blocks pointed by block1 and block2.
Returns 0 if blocks are identical, 1 if block1[i] > block2[i], -1 if block1[i] < block2[i].
vlad007700BC/my_string.h,vlad007700BC/my_string.h