Repair Priority is very Slow

[slibby]

For any area with a substantial number of points needing repair (SL for example), Repair Priority is very slow as it runs at no more than 1 pt/ 3seconds. Will need to look into the iteration in the script to see if it can be improved.

https://github.com/dcgull/WPDx-Toolset/blob/master/WPDx_Toolset.pyt#L366 is where to start.

[dcgull]

Right now we iterate through points one by one because ZonalStatisticsAsTable doesn't work when the zones overlap each other. Should be possible to speed this up by running ZonalStatisticsAsTable on all the non-overlapping water points first, then only going through the remainder one-by-one.