Initial gradle setup
Create .travis.yml

This file is used by Travis CI
Update README.md

Added Travis CI build status to README.md
Added JaCoCo unit test coverage tool
Added Identifier classes, tweaked directory structure
Added newlines on files
Made everything actually... ahem... compile
Made Namespace::name immutable in the constructor
Ignore .class files in git
Made everything actually... ahem... compile... again
Added more complete .gitignore
Moved files for consistency with gradle build system (in another pull request)
Fixed argument line wrapping
Added unit tests
Fixed test naming conventions
Rejiggered namespaces
Marked classes as public
Update .gitignore
Added basic type system and Boolean type
Code review feedback