Makefile improvements

[0xTriboulet]

Bin/temp should be .gitkeep'd so the make file can run successfully out of the box.

Adding -Wno-int-conversion -Wno-incompatible-pointer-types to CFLAGS lets this build on more modern mingw versions

Great work

[NtDallas]

Thanks, i have push an update on make and readme for compilation information :)