Static method and variable support on UdonSharpBehaviours and imported user types

[MerlinVR]

Link all static variables into a global memory space and generate the linkages to the correct parts of the memory space after all programs have been emitted.

Static methods just work via pulling them in via referenced methods from the root UdonSharpBehaviour methods.

• [x] Static methods
• [ ] Static variables

[MerlinVR]

Currently working on linking static methods as this will be used in lieu of manually generating bound expressions for more complex internal structures and expressions. Specifically on the road to #104 , GetComponent(s)<T> on UdonSharpBehaviours will be represented as an internal method that gets imported when used.

[MerlinVR]

Update: static methods functional.