Static global scope

[p7g]

All global variables are known at compile time, so there is no need to store them in a hashmap.

The reasoning for this decision initially was to allow for usage of a value before definition in the global scope. This, however, can be implemented by putting a placeholder in the bytecode, and updating it after the desired value is defined. Once compilation for a module is finished, we can just display an error if any positions have yet to be populated.