Run lint before tests

Author: justinfagnani

package.json

@@ -13,7 +13,7 @@
     "build": "tsc",
     "gen-docs": "typedoc --readme none --mode modules --excludeNotExported --excludePrivate --exclude **/*_test.ts --out ./docs/api .",
     "pretest": "npm run posttest; ln -s node_modules bower_components",
-    "test": "wct -l chrome",
+    "test": "npm run lint && wct -l chrome",
     "posttest": "rm -f bower_components",
     "checksize": "uglifyjs lit-html.js -mc --toplevel | gzip -9 | wc -c",
     "format": "find src test | grep '\\.js$\\|\\.ts$' | xargs clang-format --style=file -i",