* Move the reexec parts of lib/srv to session/reexec
* Update references to the moved bits of lib/srv
* Avoid testutils in session/reexec
* Shuffle some constants around to avoid imports in session/reexec
* Vendor in the relevant parts of logutils in session/reexec
* Remove unnecessary symlink checks when opening files
* Inline the last two things from lib/utils in session/reexec
* Inline moved constants
* Deprecate group name consts and fix missed inlines
* Add missing session/reexec.TestMain with reexec check
* Reuse existing constants from the log constants package in session
* Fix broken godoc link
* GitHub proxy part 6: proxing Git using SSH transport
* better command parsing and update suite
* refactor
* revert unnecearrty files
* address review comments
* ut fix
* revert localsite_test.go
* change special suffix to teleport-github-org for routing
* fix routing ut
* minor typo edit
* fix ut after sshca change
* add UT to sshutils
* minor review comments
* fix api ut because of special suffix change
* GitServerReadOnlyClient
* downgrade error to warning
* run go mod tidy. not sure why it's needed
* rename mock.go to mock_test.go
Edoardo Spadolini