test(scanner): port the rest of the lexer tests from AngularDart

Closes #64
chore(karma): use ChromeCanary as the default for JS

Closes #56
chore: use es6-module-loader

Switch Traceur to use modules=“instantiate” and use es6-module-loader.
This setup supports cyclic dependencies.
transpiler: normalize Dart library name

`file2module` was used for normalizing paths where `-` is fine.
This normalizes non-word characters only when generating the Dart
library name.
test(transpiler): add a cycle import spec