miss-islington can also do regular non-backport merges (#262)

* miss-islington can also do regular non-backport merges

Add the information to README that miss-islington can also merge regular PRs if `automerge` label is added to them and it is approved by a Core Dev.

* Remove some redundant info.

* Add robo emoji

Co-Authored-By: Mariatta <[email protected]>

Author: maxking

README.rst

@@ -10,7 +10,7 @@ miss-islington
 
 🐍🍒⛏🤖
 
-Bot for backporting `CPython <https://github.com/python/cpython/>`_ Pull Requests.
+Bot for backporting and merging `CPython <https://github.com/python/cpython/>`_ Pull Requests.
 
 miss-islington requires Python 3.6. Python 3.7 is not yet supported.
 
@@ -34,6 +34,14 @@ Merging the Backport PR
 If a Python core developer approved the backport PR made by miss-islington, it will be
 automatically merged once all the CI checks passed.
 
+
+Merging PRs
+===========
+
+If a Python core developer approved a PR made by anyone and added the "🤖 automerge" label,
+it will be autmatically merged once all the CI checks pass.
+
+
 **Aside**: where does the name come from?
 =========================================