docs: update CHANGELOG for 2.8

docs/changelog.rst

@@ -6,8 +6,8 @@ Changelog
 Starting with version 1.8.0, pybind11 releases use a `semantic versioning
 <http://semver.org>`_ policy.
 
-v2.8.0 (WIP)
-------------
+v2.8.0 (Oct 4, 2021)
+--------------------
 
 New features:
 
@@ -46,13 +46,17 @@ New features:
   references instead of copies.
   `#3293 <https://github.com/pybind/pybind11/pull/3293>`_
 
+* Improve the classes generated by ``bind_map``: `#3310 <https://github.com/pybind/pybind11/pull/3310>`_
+    * Change ``.items`` from an iterator to a dictionary view.
+    * Add ``.keys`` and ``.values`` (both dictionary views).
+    * Allow ``__contains__`` to take any object.
+
 * ``pybind11::custom_type_setup`` was added, for customizing the
   ``PyHeapTypeObject`` corresponding to a class, which may be useful for
   enabling garbage collection support, among other things.
   `#3287 <https://github.com/pybind/pybind11/pull/3287>`_
 
 
-
 Changes:
 
 * Set ``__file__`` constant when running ``eval_file`` in an embedded interpreter.
@@ -106,6 +110,9 @@ Build system improvements:
 * Fix a harmless warning from CMake 3.21 with the classic Python discovery.
   `#3220 <https://github.com/pybind/pybind11/pull/3220>`_
 
+* Eigen repo and version can now be specified as cmake options.
+  `#3324 <https://github.com/pybind/pybind11/pull/3324>`_
+
 
 Backend and tidying up: