Add a README

Signed-off-by: Johannes Schindelin <[email protected]>

Author: dscho

README.md

@@ -0,0 +1,5 @@
+# A mirror of the Git mailing list
+
+This is actually a mirror of the Git mailing list mirror at https://lore.kernel.org/git. Since that mirror chunks the archive by epochs, this mirror fetches each epoch into its own branch: the oldest epoch into `lore-0`, the next one into `lore-1`, etc.
+
+As scheduled workflows _must_ live in the default branch, this mirror's main branch is the one containing the workflow, this `README.md` and nothing else.