Create script to autogenerate x64 base addresses

Currently we have a script to autogenerate DLL base addresses for x86.
For x64 the base addresses are manually created.
While on x64 it is less of an issue (since the address space is huge enough to be wasteful when assigning base addresses), it would be good to have a script there as well, to avoid having to fix base addresses manually.
When implementing such a script, the free space can be larger than on x86.