Describe tag character sets better
Fix empty array handling in acid_set_from_iarr
Verify git dir in acid_git_load
Use target branch as rev_old with new references
Fix wrong comment on acid_repo_ref_update output
Clarify how updated repo is referenced

Clarify how updated repo is referenced by acid_repo_ref_update.
Normalize reference with the updated repo
Accept pushes to refs/heads directly
Implement acid_repo_ref_update script invocation
Implement repo update handling
Enable aborting the executable in acid-strict-env
Switch executables to the new library