For example, "emacs-23" for Emacs 23.2 and later, "EMACS_23_1_RC" for
23.1, "EMACS_22_BASE" for 22.x, and "EMACS_21_1_RC" for 21.x.
-Traditionally only bug-fixes were allowed in minor releases.
-Recently (22.x, 23.2), self-contained new features were allowed on a
-case-by-case basis.
+Consult emacs-devel for exactly what kinds of changes are allowed
+on what branch at any time.
If you are looking at this file in a branch other than the trunk,
there may be some branch-specific documentation below this line.