Clean dist_tests before starting tests

Author: darcyparker

package.json

@@ -10,7 +10,7 @@
     "build-tests": "tsc -p ./tsconfig.test.json",
     "watch": "tsc -p ./tsconfig.json --watch && tsc -p ./tsconfig.test.json --watch",
     "lint": "tslint -c tslint.json src/*.ts",
-    "test": "npm run build-tests && ava",
+    "test": "rm -rf dist_test && npm run build-tests && ava",
     "tdd": "npm run watch & ava --watch",
     "prepublish": "npm run build"
   },