add docs about setting up search

README.md

@@ -13,3 +13,24 @@ Installation
 - Run `app/console assets:install web` to deploy the assets on the web dir.
 - Make a VirtualHost with DocumentRoot pointing to web/
 - You should now be able to access the site, create a user, etc.
+
+Setting up search
+-----------------
+
+The search index uses [Solr](http://lucene.apache.org/solr/), so you will have to install that on your server.
+If you are running it on a non-standard host or port, you will have to adjust the configuration. See the
+[NelmioSolariumBundle](https://github.com/nelmio/NelmioSolariumBundle) for more details.
+
+You will also have to configure Solr. The standard `schema.xml` already covers most fields like `title` and
+`description`. The following need to be added though:
+
+    <fields>
+        ...
+
+        <field name="tags" type="text_general" indexed="true" stored="true" multiValued="true"/>
+
+        ....
+    </fields>
+
+To index packages, just run `app/console packagist:index`. It is recommended to set up a cron job for
+this command, and have it run every few minutes.