Speed up Moore initialization (XML reading)
Avoid using DOMNodeList::getLength()
for a speedup of about x2
(or 30 s) in the XML reading for loading geometry/conditions.
This dominates the initialization, which is sped up correspondingly.
More (sligthly less trivial) optimizations are possible.
This is very old code that is going to be made obsolete with Detector/DD4hep. However, initialization takes a considerable time when testing both centrally and locally (we have >100 tests in Moore), so it is worth improving that now.
Edited by Rosen Matev