Adds an interface and implementation for scope management.
Removes some false documentation.
Changes HekateScriptVisitor to use dependency injection for the virtual machine and scope manager.
Adds the implementation for VisitVariableDeclaration and adds a test for it.
Fixes the virtual machine assigning indices incorrectly to newly added variables .
Extracts a setup method for mocking out the current scope (and adds a setup method).
Adds the implementation for VisitAssignmentExpression and adds tests for it.
Adds an enum for identifier types.
Fixes a variable value to be more relevant to what's being tested.