Add hint on merging

Author: koppor

README.md

@@ -25,7 +25,7 @@ For user documentation, please head to <https://adr.github.io/madr/>.
 | Branch | Meaning |
 | -- | -- |
 | `gh-pages` | Homepage showing the latest released version, rendered at <https://adr.github.io/madr> |
-| `develop` | Latest developments, including homepage updates which should be published on a release |
+| `develop` | Latest developments, including homepage updates which should be published on a release. `gh-pages` should always be merged into this branch. |
 | `release/v1` | Branch for latest release 1.x version of MADR. Introduced to fix [#92](https://github.com/adr/madr/issues/92) |
 | `release/vY` | Branch for version Y.x of MADR. |