manifest: Add syntax for creating symbolic links in the guest image

The following:

  /lib: ->/lib.1.0

Will create /lib linked to /lib.1.0

Reviewed-by: Nadav Har'El <nyh@cloudius-systems.com>
Signed-off-by: Tomasz Grabiec <tgrabiec@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>
cpio: Log creation of symbolic links

We log adding files, let's also log creating links for consistency.
Useful in debugging builds.

Reviewed-by: Nadav Har'El <nyh@cloudius-systems.com>
Signed-off-by: Tomasz Grabiec <tgrabiec@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>
modules: Add syntax for creating symbolic links

The following:

  usr_files.link('/lib').to('/lib.1.0')

will result in creation of '/lib' linked to '/lib.1.0' in the guest
file system.

Reviewed-by: Nadav Har'El <nyh@cloudius-systems.com>
Signed-off-by: Tomasz Grabiec <tgrabiec@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>
modules: java: Simplify creation of links

Reviewed-by: Nadav Har'El <nyh@cloudius-systems.com>
Signed-off-by: Tomasz Grabiec <tgrabiec@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>