docs: add v2020.1.1 release notes

(cherry picked from commit 1566324f)

docs/index.rst

@@ -74,6 +74,7 @@ Several Freifunk communities in Germany use Gluon as the foundation of their Fre
    :caption: Releases
    :maxdepth: 1
 
+   releases/v2020.1.1
    releases/v2020.1
    releases/v2019.1.2
    releases/v2019.1.1

docs/releases/v2020.1.1.rst

+Gluon 2020.1.1
+==============
+
+This is the first service release for the Gluon 2020.1.x line, fixing regressions reported by
+the community.
+
+Bugfixes
+--------
+
+- Fixed non-working LEDs on TP-Link Archer C5 v1 and Archer C7 v2 after an upgrade to Gluon 2020.1.
+
+- Fixed an issue which leads to AVM FRITZ!WLAN Repeater 450E devices being stuck in failsafe mode
+  ater an upgrade to Gluon 2020.1.
+
+Other changes
+-------------
+
+- Linux kernel has been updated to 4.14.171
+
+Known issues
+------------
+
+- Out of memory situations with high client count on ath9k.
+  (`#1768 <https://github.com/freifunk-gluon/gluon/issues/1768>`_)
+
+- The integration of the BATMAN_V routing algorithm is incomplete.
+
+   - | Mesh neighbors don't appear on the status page. (`#1726 <https://github.com/freifunk-gluon/gluon/issues/1726>`_)
+     | Many tools have the BATMAN_IV metric hardcoded, these need to be updated to account for the new throughput
+     | metric.
+
+   - | Throughput values are not correctly acquired for different interface types.
+     | (`#1728 <https://github.com/freifunk-gluon/gluon/issues/1728>`_)
+     | This affects virtual interface types like bridges and VXLAN.
+
+- Default TX power on many Ubiquiti devices is too high, correct offsets are unknown
+  (`#94 <https://github.com/freifunk-gluon/gluon/issues/94>`_)
+
+  Reducing the TX power in the Advanced Settings is recommended.
+
+- The MAC address of the WAN interface is modified even when Mesh-on-WAN is disabled
+  (`#496 <https://github.com/freifunk-gluon/gluon/issues/496>`_)
+
+  This may lead to issues in environments where a fixed MAC address is expected (like VMware when promiscuous mode is
+  disallowed).
+
+- Inconsistent respondd API (`#522 <https://github.com/freifunk-gluon/gluon/issues/522>`_)
+
+  The current API is inconsistent and will be replaced eventually. The old API will still be supported for a while.
+
+- Frequent reboots due to out-of-memory or high load due to memory pressure on weak hardware especially in larger
+  meshes (`#1243 <https://github.com/freifunk-gluon/gluon/issues/1243>`_)
+
+  Optimizations in Gluon 2018.1 have significantly improved memory usage.
+  There are still known bugs leading to unreasonably high load that we hope to
+  solve in future releases.
+
+- High chance of ending in a soft-bricked state for Ubiquiti EdgeRouter-X. Workaround is to
+  repeat initial installation using the serial console. (`#1937 <https://github.com/freifunk-gluon/gluon/issues/1937>`_)