Expand developer console documentation

Issue Description
Documentation for dev console is extremely limited, which makes understanding what it tells you significantly harder than it needs to be. The current article only highlights 3/9 categories that the developer console can tell you about.

This excludes the additional categories that contain data that could be useful, but it is unclear how the data is read. For example, it would be great to know what the numbers inside of the data store category represent:

No clue what I’m reading when it only displays “value”, but with some digging I was able to learn that this reflects what the GetRequestBudgetForRequestType API returns.

The scripts category could also use more clarification. It’s unclear what the “Rate (/s)” column represents.

Issue Area: DevHub Content
Page URL: Developer Console