[maven-release-plugin] prepare release 0.3.0

pom.xml

 <?xml version="1.0" encoding="UTF-8"?>
-<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
 	<modelVersion>4.0.0</modelVersion>
 
 	<artifactId>c2mon-web-atmosphere</artifactId>
-	<version>0.3.0-SNAPSHOT</version>
+	<version>0.3.0</version>
 	<packaging>jar</packaging>
 
 	<name>Atmosphere publisher for C2MON</name>
@@ -20,7 +19,7 @@
         <url>https://gitlab.cern.ch/c2mon/c2mon-web-atmosphere</url>
         <connection>scm:git:ssh://git@gitlab.cern.ch/c2mon/c2mon-web-atmosphere.git</connection>
         <developerConnection>scm:git:ssh://git@gitlab.cern.ch:7999/c2mon/c2mon-web-atmosphere.git</developerConnection>
-        <tag>HEAD</tag>
+        <tag>0.3.0</tag>
     </scm>
 
 	<properties>