Templates changes and fixes

* configuration: use `adminUrl` instead of `opensdi2ManagerUrl` in managerConfig.js
* css: Insert the `<style>` prefix and `</style>` suffix to the css inserted by the user
* now opensdi-manager2 is called through proxy
* rename the "Reset" button to "New"
Categories initialization on mapstore

Add `TEMPLATE` category to the categories initialization for mapstore.