Bug 615: Removed xtend from Topology Manager

Rewriten Topology Exporter to Java code, added synchronized blocks
to critical pieces of code, which created conflicting transactions

Change-Id: I8d9cad2e0f6edfd2440d134ec0e2b670c16470b4
Signed-off-by: Tony Tkacik <ttkacik@cisco.com>
Signed-off-by: Robert Varga <rovarga@cisco.com>
Merge "Bug 615: Removed xtend from Topology Manager"