Improvements related to all commands

[billygriffin]

There are several things that we'd like to make improvements on that apply to all our commands, so I wanted to organize those so we have a checklist to help guide our efforts. Feel free to update this issue to make it as useful as possible.

These four areas are applicable to all our commands, and therefore doing them all might be more efficient than doing them one by one.

• Ensure commands are scriptable and, where possible, the output should be able to be used to pipe to other commands Scriptability audit #940
• Ensure commands use named API queries to help us understand what commands are most widely used overall, and what load we're putting on the API Give names to all our GraphQL queries #997
• Refactor commands into isolated units: Restructure commands in isolated units #770
• Ensure the commands work appropriately for GitHub.com and GitHub Enterprise hosts, including conditional querying to provide backward compatibility for older GHES versions Support for GitHub Enterprise #273

In rough order of ascending complexity:

• gist
• alias
• config
• repo
• issue
• pr

[vilmibm]

Assigning myself to indicate that I'm working on #940

[vilmibm]

I'll also be taking on #770 with mislav's help

[mislav]

Closing this tracking issue since most of its components are done, and GHE work is being tracked in #1180 and #1102.