[TASK] Add ability to test other raven installations

[j-bryan]

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Issue Description

Is your feature request related to a problem? Please describe.
It would be nice to be able to run the raven tests on installations of raven besides the development version. This includes pip installations and executables of raven. Right now, there is no easy way to point the rook testing infrastructure to a different version of raven.

Describe the solution you'd like
Edit the testing infrastructure (rook and TestHarness classes) to allow the user to point rook to a different installation of raven.

Describe alternatives you've considered
Use different versions of raven_framework.py (for example) to point raven execution to other places.

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For Change Control Board: Issue Review

This review should occur before any development is performed as a response to this issue.

• 1. Is it tagged with a type: defect or task?
• 2. Is it tagged with a priority: critical, normal or minor?
• 3. If it will impact requirements or requirements tests, is it tagged with requirements?
• 4. If it is a defect, can it cause wrong results for users? If so an email needs to be sent to the users.
• 5. Is a rationale provided? (Such as explaining why the improvement is needed or why current code is wrong.)

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For Change Control Board: Issue Closure

This review should occur when the issue is imminently going to be closed.

• 1. If the issue is a defect, is the defect fixed?
• 2. If the issue is a defect, is the defect tested for in the regression test system? (If not explain why not.)
• 3. If the issue can impact users, has an email to the users group been written (the email should specify if the defect impacts stable or master)?
• 4. If the issue is a defect, does it impact the latest release branch? If yes, is there any issue tagged with release (create if needed)?
• 5. If the issue is being closed without a pull request, has an explanation of why it is being closed been provided?