More general versions

Author: APN-Pucky

src/main/java/de/neuwirthinformatik/Alexander/GitJarUpdate/Version.java

@@ -15,7 +15,9 @@ public Version(String version) {
         if(version == null)
             throw new IllegalArgumentException("Version can not be null");
         if(!version.matches("[0-9]+(\\.[0-9]+)*"))
-            throw new IllegalArgumentException("Invalid version format");
+            throw new IllegalArgumentException("Invalid version format: " + version);
+        if(!version.matches("v[0-9]+(\\.[0-9]+)*"))
+        	version = version.substring(1);
         this.version = version;
     }