added documentation for new display model

Author: JonasB2497

components/display/waveshare_epaper.rst

@@ -108,6 +108,7 @@ Configuration variables:
   - ``7.50in``
   - ``7.50in-bV2`` - also supports v3, B/W rendering only
   - ``7.50in-bV3`` - display with the '(V3)' sticker on the back, B/W rendering only
+  - ``7.50in-bV3-bwr`` - display with the '(V3)' sticker on the back, BWR rendering enabled (uses double the amount of RAM for the display buffer as B/W rendering)
   - ``7.50in-bc`` - display with version sticker '(C)' on the back, B/W rendering only
   - ``7.50inV2`` - Can't use with an ESP8266 as it runs out of RAM
   - ``7.50inV2alt`` (alternative version to the above ``7.50inV2``)