Update to support x64 bit games

[FortyTwoFortyTwo]

There is some massive changes on how the way the core part of the plugin works, so the version gets a 2.0.0 bump.

First step for x64 bit support is to make use of virtual address from latest Sourcemod update, using LoadAddressFromAddress and StoreAddressToAddress.

Using virtual address however makes it that the hack on getting address from VTable no longer works, with no simple workaround solution for it. All of the detour usages on IScriptVM from offset therefore have to be replaced with a virtual hook. A few signatures had to be added to gamedata to get it working, hopefully aside from L4D2 all of the other games should have the same windows signatures.

No address from VTable also makes it that native VScriptFunction.Function.get now returns null if its an offset function, users will need to create a virtual hook instead.

This PR cannot be merged yet as sourcescramble extension will need to be updated to support virtual address, and having natives to be able to load/store address from MemoryBlock. DHooks also still has yet to support 64bit and having address support for ReturnType and HookParamType.