Instance wide code statistics
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### Problem to solve
As a CIO of a large bank, I may want to understand what programming languages are used throughout my organization of 8, 10,000 developers. Today GitLab shows at the project level what percentage of the code is a given programming language. But it would be nice to be able to see this in the aggregate (group level, instance level, etc.
I may also want to see things like:
* Lines of code (and trends)
* Code coverage group/instance wide
* Code quality group/instance wide
(these may or may not need to be their own issue)
### Further details
Talked to a large banking industry customer about this with @xyzzy
### Proposal
### What does success look like, and how can we measure that?
(If no way to measure success, link to an issue that will implement a way to measure this)
### Links / references
issue