Heroku integration with foreman

Add foreman configuration for Heroku:
- To test production configuration execute NODE_ENV=production foreman
  start
- Database connection configuration now handles "use_env_variable" which
  should be defined as a environment variable such as "DATABASE_URL"
  with a proper database URI connection string, ie:
  postgres://user:password@db.example.com:5432/database
- Added package.json configuration to run migrations and db seed after
  `npm install`

Update frontend models to match sequelize definition.
Update views to work according to the changes above.
Handling isCompleted and parentId apropiately for PostgreSQL databases

package.json

@@ -5,12 +5,14 @@
     "dependencies": {
         "express": "~3.1.0",
         "path": "~0.4.9",
-        "mysql": "~2.0.0",
-        "sqlite3": "~2.1.0",
+        "pg": "~3.4.1",
         "sequelize": "~1.7.9",
         "socket.io": "~1.0.6",
         "config": "~1.0.2"
     },
+    "devDependencies": {
+        "sqlite3": "~2.1.0"
+    },
     "engines": {
         "node": "0.10.x"
     },