requires() helper does not always support context correctly

[notmessenger]

Attempting to replace the testing code at
https://github.com/softlayer/sl-ember-translate/blob/923c681ba54cf65e46f7280b0fb65c6b13f24495/tests/unit/services/translate-test.js#L25-110 with

var test = requires( TS.setDictionary, [ 'object' ] );
assert.ok( test.requires, test.messages );

"this" does not exist (https://github.com/softlayer/sl-ember-translate/blob/e6666ff06ad6959600f60f9c0fe5bb1c840527f7/addon/services/translate.js#L51)

[notmessenger]

https://github.com/softlayer/sl-ember-behavior/blob/cf80ec3ddab12eb5f691f171b33e3f8bdff231d4/tests/unit/services/behavior-test.js#L16-89 has the same issue and several other instances in the same file as well

[notmessenger]

Will be resolved by #126