Revert "[maven-release-plugin] prepare for next development iteration"

This reverts commit 9aa1583eb2fde4a0fa6a95f3bcab40222918398a.
diff --git a/hyracks-fullstack/hyracks/hyracks-storage-am-rtree/pom.xml b/hyracks-fullstack/hyracks/hyracks-storage-am-rtree/pom.xml
index 46ea703..85102e3 100644
--- a/hyracks-fullstack/hyracks/hyracks-storage-am-rtree/pom.xml
+++ b/hyracks-fullstack/hyracks/hyracks-storage-am-rtree/pom.xml
@@ -25,7 +25,7 @@
   <parent>
     <groupId>org.apache.hyracks</groupId>
     <artifactId>hyracks</artifactId>
-    <version>0.2.19-SNAPSHOT</version>
+    <version>0.2.18</version>
   </parent>
 
   <licenses>