Exit with non-zero for unknown commands.
Merge pull request #2816 from rwjblue/fail-build

Exit with non-zero for unknown commands.
Allow test framework addons to override query string.
Merge pull request #2820 from rwjblue/test_page-query-string-abstraction

Allow test framework addons to override query string.
Bump ember-cli-dependency-checker to v0.0.7

This also fixes #2591.
Merge pull request #2821 from quaertym/patch-15

Bump ember-cli-dependency-checker to v0.0.7