Move app config files to new name

element.io/README

@@ -1,11 +1,12 @@
 This directory contains the config files and deployment scripts for the official
-riot.im distribution of Riot Web at https://riot.im.
+element.io distribution of Element Web.
 
 You probably do not want to build with this config unless you're building the
-official riot.im distribution, but these files may be useful if you want to
+official element.io distribution, but these files may be useful if you want to
 inspect the configuration used there.
 
-Riot Desktop uses a separate config (see https://github.com/vector-im/riot-desktop/tree/develop/riot.im).
+Element Desktop uses a separate config (see
+https://github.com/vector-im/riot-desktop/tree/develop/element.io).
 
 Deployment scripts (such as app/deploy.py) are meant to be run on the web server
-hosting the Riot installation.
+hosting the Element installation.