Fix link to description file (#45)

maratori · SergeyPirogov · commit dd55dbea1d7f · 2018-05-13T18:25:51.000+03:00
diff --git a/setup.cfg b/setup.cfg
@@ -2,4 +2,4 @@
 universal = 1
 
 [metadata]
-description-file = README.md
+description-file = README.adoc
