Remove all occurrences of 'rugged' from Repository

https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/16656 introduces a check for the word 'rugged'. app/models/repository.rb still fails the check. We should make the check pass.

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Stages:

• RPC Design: Create Issue

• ~"Client Implementation": Create Issue

• Server Implementation: Create Issue

• ~"Acceptance Testing": Create Issue

RPC Endpoints:

• Endpoint::Name

Known Client Routes:

• Known client endpoints

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