feat(transpiler): Transform template strings to triple quoted Dart strings
docs(di): simple typo
fix(lang): fix small typo.
feat(compiler): initial version of the compiler.

Supports:
- binds text nodes, element properties and directive properties
- locates decorator, component and template directives.
- inline templates of components

The compiler is built using a pipeline design,
see core/src/compiler/pipeline package.

Integration tests to show how the compiler, change_detection and DI work
together:
core/test/compiler/integration_spec.js