fix grunt-compare-size dependency to v0.2.0

Checking out the tag **1.8.3** and installing dependencies via `npm install` leads to **v3.0.1** of **grunt-compare-size**. However, the last compatible version of **grunt-compare-size** is **v.0.2.0**. 

Please merge this small change in package.json and update the jquery tag **1.8.3**, otherwise it's not possible to build jquery from scratch using this tag.