The current documentation at restic.readthedocs.io does not contain a proper troubleshooting section, where users can find common problems and how to (initially) handle them. This needs to be addressed.

I propose the following:

• Use the FAQ as the starting point.
• Replace the items in the FAQ that are about specific error messages with a reference to the new troubleshooting section.
• Make sure to cover what's currently in the FAQ in the new troubleshooting section.
• Make sure that the troubleshooting section references the forum as a place to get further help if the troubleshooting section isn't sufficient, and the issue tracker as a place to report what the user believes is a bug.
• Once we have the troubleshooting section in place, in the various commands of restic, update the current references to creating a new issue/bug report, so that they instead point to the troubleshooting section in the documentation.

This issue supersedes issues #1813 and #2361.