v2.9.0
Drop support for Handlebars template compilation

 * always use custom template compiler
 * remove `I18N_COMPILE_WITHOUT_HANDLEBARS` feature flag
 * don't run tests with `WITHOUT_HANDLEBARS=true`
 * update dependencies documentation to indicate that only
   Handlebars-runtime is needed
Merge pull request #163 from jamesarosen/james/no-hdbs-compilation

Drop support for Handlebars template compilation
Drop support for CLDR.js

 * JSHint: CLDR is no longer defined
 * `Ember.I18n.locale` no longer falls back to `CLDR.defaultLanguage`
 * `Ember.I18n.pluralForm` no longer defaults to `CLDR.pluralForm`
Merge pull request #164 from jamesarosen/james/no-cldr

Drop support for CLDR.js