SLING-3660 - Refine 'connected' state of a (vlt) repository, cache node
types after disconnection properly

Update ContentImportTest to start the server before attempting to
import.

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1602372 13f79535-47bb-0310-9956-ffa450edef68