Finished phase 1 of the Semantic Analysis

Implemented Scope-Analysis checks. It can correctly identify and point out issues with scopes. It understands a variety of different scopes, from for-loops to functions to Sprites.

Also added support for switch-statements. Importantly, I chose to force only 1 default, and force it to be only at the end.

I also implemented true and false as a new Boolean primitive type, alongside a true return statement