Fix .classpath to make jgit easily runnable from inside eclipse

Fix .classpath to make jgit easily runnable from inside eclipse

When running jgit from inside Eclipse (e.g. rightclick on project
org.eclipse.jgit.pgm and select Run as->Java application) no commands
are found. This is because the commands are loaded from a resource file
/META-INF/services/org.eclipse.jgit.pgm.TextBuiltin and this file is
not anymore on the classpath.
I fixed this by modifying .classpath to contain the META-INF directory.

Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>