debian: add commented entries required for PPA builds & update "debianhowto" target

If someone runs "ant debian" to make installable packages, they do not need to
have their own wrapper or commons-logging  jars. The PPA builds, however, do
require them. During the last release I made the mistake of overwriting my "PPA
debian/control" file with the one from MTN that did not include these
dependencies.

Also updating "debianhowto" to reflect the fact that we no longer use
Debian's/Ubuntu's Jetty pkgs since Jetty6 appears to be leaving their repos in
the near future.

debian/control

@@ -11,6 +11,9 @@ Build-Depends: debhelper (>= 7.0.50~),
  default-jdk,
  gettext,
  libgmp3-dev,
+## uncomment the next line for PPA builds
+## libservice-wrapper-java,
+ libcommons-logging-java,
  po-debconf
 
 Package: i2p