Fixed return codegen from main function
Small codegen refactor for closures
Fixed class variables codegen. Also allow using class vars in modules.
Fixed "did you mean" sometimes raising
Better description for "-ll" option
Allow casting a fun type to another one accepting more arguments
Allow creating threads with or without an argument to pass along
Put back Array#sort_by and Array#sort_by but with fun types for now. Fixed some missing code.
Stop performing SSA on closured variable, and some fixes with fun literals normalization
A block can also be a closure context if the closured variable is declared inside it
Fixed closures in blocks
Removed CastFunToReturnVoid AST node and use a regular Cast node instead. Allow casting a function to another one that returns void.