Development: Use headings for nicer view and anchor support

Donation anchor is needed for Gajim's appdata file.

content/en/development/_index.md

@@ -17,10 +17,16 @@ Development happens on [our Gitlab](http://dev.gajim.org/gajim/gajim). Contribut
 
 You can help us make Gajim better by:
 
-* Coding: contact us on our mailing list or join our group chat [gajim@conference.gajim.org](xmpp:gajim@conference.gajim.org?join)
-* Translating: [How to translate](https://dev.gajim.org/gajim/gajim/wikis/development/DevTranslate), get involved and [start translating Gajim](https://translate.gajim.org/projects)
-* Bug reporting: in case you find a bug, do not hesitate to [report it](https://dev.gajim.org/gajim/gajim/issues/new)
-* Donating:
+### Coding
+Contact us on our mailing list or join our group chat [gajim@conference.gajim.org](xmpp:gajim@conference.gajim.org?join)
+
+### Translating
+[How to translate](https://dev.gajim.org/gajim/gajim/wikis/development/DevTranslate), get involved and [start translating Gajim](https://translate.gajim.org/projects)
+
+### Bug reporting
+In case you find a bug, do not hesitate to [report it](https://dev.gajim.org/gajim/gajim/issues/new)
+
+### Donating
   * [PayPal](https://www.paypal.com/donate/?token=eFHDaiuQ45i6ZiDz9CCv39HkBCdK3PBkDPHjk2zImuiL_OpRe2sHi1MNM80NzvEKqfLPmG&country.x=US&locale.x=US)
   * [Flattr](https://flattr.com/@Asterix)