pgm: add missing dependency to org.apache.commons.logging

Without this dependency I get class loading exceptions when trying to
run org.eclipse.jgit.pgm.Clone in Eclipse.

Change-Id: Ia9ecb385d3baccbcd041114287af5076fefd3d71
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
diff --git a/org.eclipse.jgit.pgm/META-INF/MANIFEST.MF b/org.eclipse.jgit.pgm/META-INF/MANIFEST.MF
index 1dfb418..e92c83e 100644
--- a/org.eclipse.jgit.pgm/META-INF/MANIFEST.MF
+++ b/org.eclipse.jgit.pgm/META-INF/MANIFEST.MF
@@ -8,6 +8,7 @@
 Bundle-Localization: plugin
 Bundle-RequiredExecutionEnvironment: JavaSE-1.8
 Import-Package: javax.servlet;version="[3.1.0,4.0.0)",
+ org.apache.commons.logging;version="[1.2,2.0)",
  org.eclipse.jetty.server;version="[9.4.5,10.0.0)",
  org.eclipse.jetty.server.handler;version="[9.4.5,10.0.0)",
  org.eclipse.jetty.servlet;version="[9.4.5,10.0.0)",