Changed messages based on list feedback

Changed and clarified some messages from error to warning or info. 
  The conditions were not errors.

Changed REST abstract class exception handling to differentiate 
 between REST Server not responding and invocation exception.

Change-Id: I7349f1d0c4fa3ceabfe1d7c1c006d12b269e40ab
Signed-off-by: Reinaldo Penno <rapenno@gmail.com>
Merge "Changed messages based on list feedback"