Fix leapseconds issue in dmlib version of PGD xml

[ulbergc]

• Identical binaries on eew-bk-dev1 and eew-uw-dev2 had different timestamps in the CoreEventInfo origin_time by exactly 27 seconds.
• The $LEAPSECONDS variable is defined on uw-dev2 but not bk-dev1
• The problem is somewhere in how the dmlibWrapper_createPGDXML generates xml using the dmlib
• See event id 1635205360 for example