Cache static resources to avoid re-download on every refresh

[ricardozanini]

The serverless workflow editor inside Runtime Tools needs to fetch a JS file that has around 40MB. It does so on every page refresh if no cache policy is defined. Although this is not an issue when running locally, users may experience some delays after a page refresh due to this fetch operation when running the dev mode image on a remote OpenShift instance.

The goal of this task is to create a cache policy for static files like JS and CSS so that browsers use cached resources instead of redownloading these files every time.

Here is an example of how it could be done in the dev mode image.

[domhanak]

FYI @LuboTerifaj