modifying lastUpdate to get latest date, using utility to traverse tree
* minor formatting changes
* swapped == for .equals
* added testing of comparator (very trivial)
Switched to fuzzy date comparison to account for precision mismatch between http dates and sql timestamps.
Merge pull request #802 from cschroed-usgs/CCH-1112-fuzzyComparison

Cch 1112 fuzzy comparison