BUG-1089: convert TopologyReader

This converts TopologyReader from xtend to pure Java, optimizing it
while we're at it.

Change-Id: Ide991f0bc529db0cdeb3526d4b0d4e99d8ade3c7
Signed-off-by: Robert Varga <rovarga@cisco.com>
Merge "BUG-1089: convert TopologyReader"