Bug 1966 fixed

Parsed the manifest returned by the `helm status` command (in the
`_status_kdu` method) from a raw string to a list of dictionaries (each
entry in the list corresponds to each manifest's document).

Change-Id: I791c8fd59fee8ac67bcbd640a100bf63d572efcf
Signed-off-by: Pedro Escaleira <escaleira@av.it.pt>