Javascript: replace jq with jQuery in templates too.

With PR #19 `jq` was replaced with `jQuery` in all JavaScript files, but the `.pt` files containing JavaScript were missing.
This PR adds fixes for `.pt` files.
It also fixes a `jq` occurence in `shop.js` which I was missing.

@lukasgraf can you review this?
I've not added an additional changelog because the previous PR (#19) was not released yet.