We're not using the uintptr_t type in the library
Add a check for unsigned __int128 type
Fix broken use of strcmp when I needed to use strstr

This test wasn't really testing anything useful.
Add conditional compilation for UINT128

I tested this both ways by manually disabling the -DHAS_UINT128 flag. All the
tests still pass.

I also tested that mmdblookup does something sane with uint128 types in both
cases.
All my todos are done!