Fifth Milestone: Implemented x86 Code Generation via Firm

Fifth Milestone: Implemented x86 Code Generation via Firm.

Forth Milestone: Semantic Analysis Implemented

Forth Milestone: Semantic Analysis Implemented.

Third Milestone: AST Generation and PrettyPrinter

This is the third milestone. The Parser now generates the AST and the PrettyPrinter can print the AST to code.

Second milestone: Parser

This is the second milestone, the parser checks the grammar.

First milestone: Lexer

This is the first milestone, the lexer is finished.