Revert "added coveralls"

This reverts commit 8edc3d1.

Author: bmuenzenmeyer

package.json

@@ -21,7 +21,6 @@
     "graphlib": "^2.1.1"
   },
   "devDependencies": {
-    "coveralls": "^2.12.0",
     "eslint": "^3.5.0",
     "rewire": "^2.5.2",
     "tap": "^7.1.2"
@@ -56,7 +55,7 @@
   "license": "MIT",
   "scripts": {
     "lint": "eslint core/**/*.js",
-    "pretest": "npm run lint",
+    "pretest" : "npm run lint",
     "test": "tap test/*_tests.js --reporter spec --coverage"
   },
   "engines": {