Bump ember-template-lint.

Incorporates fix for "empty errors" https://github.com/rwjblue/ember-template-lint/pull/250

Author: pschutz93

package.json

@@ -33,7 +33,7 @@
     "chalk": "^2.0.1",
     "debug": "^2.6.8",
     "ember-cli-version-checker": "^2.0.0",
-    "ember-template-lint": "^0.8.0",
+    "ember-template-lint": "^0.8.1",
     "json-stable-stringify": "^1.0.1",
     "md5-hex": "^2.0.0",
     "strip-ansi": "^4.0.0",