[BUGFIX release] Ensure exports are setup for node build.
[Bugfix beta] ensure pushUnique targetQueue is cleared by flush
Merge pull request #5490 from stefanpenner/fix-bb

[Bugfix beta] ensure pushUnique targetQueue is cleared by flush
remove unused vars and enforce in jshint
Merge pull request #5475 from emberjs/unused-jshint-vars

remove unused vars and enforce in jshint
Merge pull request #5489 from rwjblue/ensure-exports-for-nodeland

[BUGFIX release] Ensure exports are setup for node build.
[BUGFIX beta] instrument should still call block even if no subscribers