Remove unused parts

Now need to fill up all patterns
Support simple types e.g. DUs, Enums and Records

Need to create more string constants
Treat type annotation declaration
Handle most of cases in expressions
Move some new examples to tests

Patterns are more or less complete.
Add assembly information
Create front end application with opts and prefs
Add more tests and various bug fixes
Merge pull request #1 from dungpa/develop

The change is sensible to make