New servlet structure with a dedicated class UmlDiagramService to

produce diagram from a compressed source.

src/net/sourceforge/plantuml/servlet/SvgServlet.java

@@ -0,0 +1,27 @@
+package net.sourceforge.plantuml.servlet;
+
+import net.sourceforge.plantuml.FileFormat;
+
+/* 
+ * SVG servlet of the webapp.
+ * TODO.
+ */
+@SuppressWarnings("serial")
+public class SvgServlet extends UmlDiagramService {
+
+    @Override
+    public String getSource( String uri) {
+        String[] result = uri.split("/svg/", 2);
+        if (result.length != 2) {
+            return "";
+        } else {
+          return result[1];
+        }
+    }
+
+    @Override
+    FileFormat getOutputFormat() {
+        return FileFormat.SVG;
+    }
+
+}