Update plugin metadata for publication

Catchment/metadata.txt

@@ -1,13 +1,13 @@
 [general]
 name=Catchment
-description=
-about=
-version=0.0.1
-qgisMinimumVersion=3.10
-author=
-email=
+description=Calculate point catchment areas (isochrones) using Graphhopper on OpenStreetMap roads
+about=This plugin requires access to a Graphhopper API (https://www.graphhopper.com), or your own Graphhopper deployment (https://github.com/GispoCoding/graphhopper-docker).
+version=0.1.0
+qgisMinimumVersion=3.16
+author=Gispo Ltd.
+email=riku@gispo.fi
 changelog=
-tags=
+tags=catchment area,graphhopper,catchment,isochrone
 repository=https://github.com/GispoCoding/catchment-plugin
 homepage=https://github.com/GispoCoding/catchment-plugin
 tracker=https://github.com/GispoCoding/catchment-plugin/issues