Add some examples for the OSM plugin

Note that these examples are intended to be used more for testing and fixing
the plugin, rather than demonstrating its functionality.

doc/plugins/osm.mdwn

@@ -15,6 +15,22 @@ if the [[!cpan JSON]] perl module is installed.
 
 This provides the [[ikiwiki/directive/waypoint]] and [[ikiwiki/directive/osm]] directives.
 
+### Examples
+
+A [[basic set of examples|http://cbaines.net/osm-examples]] is available
+([[repository|http://git.cbaines.net/?p=ikiwiki/osm-examples.git;a=summary]]).
+Note that none of these will work without patching the plugin. With the
+following patches, most of the examples will work (while each patch is
+seperate, the branch includes all previous patches in the list, so the
+cbaines/osm-icon-fixes branch includes all patches).
+
+ - [[bugs/osm plugin error TypeError: mapProjection is null]]
+ - [[todo/osm plugin GeoJSON popup patch]]
+ - [[todo/osm plugin icon patch]]
+
+Even with these patches, the CSV examples do not work, and there are cosmetic
+issues with a few of the other examples.
+
 ---
 
 The plugin was originally written by