Update SOP implementation to the latest spec version

See https://datatracker.ietf.org/doc/html/draft-dkg-openpgp-stateless-cli-03

sop-java/src/main/java/sop/operation/Version.java

@@ -8,15 +8,42 @@ public interface Version {
 
     /**
      * Return the implementations name.
+     * e.g. "SOP",
      *
      * @return implementation name
      */
     String getName();
 
     /**
-     * Return the implementations version string.
+     * Return the implementations short version string.
+     * e.g. "1.0"
      *
      * @return version string
      */
     String getVersion();
+
+    /**
+     * Return version information about the used OpenPGP backend.
+     * e.g. "Bouncycastle 1.70"
+     *
+     * @return backend version string
+     */
+    String getBackendVersion();
+
+    /**
+     * Return an extended version string containing multiple lines of version information.
+     * The first line MUST match the information produced by {@link #getName()} and {@link #getVersion()}, but the rest of the text
+     * has no defined structure.
+     * Example:
+     * <pre>
+     *     "SOP 1.0
+     *     Awesome PGP!
+     *     Using Bouncycastle 1.70
+     *     LibFoo 1.2.2
+     *     See https://pgp.example.org/sop/ for more information"
+     * </pre>
+     *
+     * @return extended version string
+     */
+    String getExtendedVersion();
 }