- renamed assembler_runner to just assembler

- implemented type parsing including custom types and generics (useless
  for now as we do no semantic analysis)
- implemented struct literal parsing
- implemented struct definition parsing (no generics yet)
- implemented tuple parsing
- registers are now allocated starting from zero
- updated to-dos

compiler/src/frontend/dsc/lexer.rs

@@ -18,6 +18,7 @@ pub enum Token {
     Const,
     As,
     SizeOf,
+    Struct,
 
     // Identifiers and literals
     Identifier(Name),
@@ -104,6 +105,7 @@ impl Token {
             Token::Const => "Const",
             Token::Static => "Static",
             Token::Include => "Include",
+            Token::Struct => "Struct",
             Token::Fn => "Fn",
             Token::If => "If",
             Token::Let => "Let",
@@ -376,6 +378,7 @@ impl<'a> Lexer<'a> {
             "static" => Some(Token::Static),
             "as" => Some(Token::As),
             "sizeof" => Some(Token::SizeOf),
+            "struct" => Some(Token::Struct),
             _ => None,
         }
     }