Fixed attribute serialization bug (at leat for non-spans)

Change-Id: I2bb46509d71450238812e4d0a26c5690dd51d49d
diff --git a/pom.xml b/pom.xml
index 4a1e534..aefc631 100644
--- a/pom.xml
+++ b/pom.xml
@@ -25,7 +25,7 @@
 
   <groupId>de.ids_mannheim.korap</groupId>
   <artifactId>Krill</artifactId>
-  <version>0.55</version>
+  <version>0.55.1</version>
   <packaging>jar</packaging>
 
   <name>Krill</name>