add Fill operation to hydrology
add test for fill operation in hydrology
add Fill operation to hydrology
fixes
Merge remote-tracking branch 'upstream/master' into hydrology
fix Fill opertaion
fixing issues
Merge remote-tracking branch 'markko/hydrology'
Fixes to syntax and other things.
Merge remote-tracking branch 'upstream/master' into hydrology
Merge pull request #1 from lossyrob/fillop

Fillop
Merge branch 'hydrology' of https://github.com/Markko/geotrellis into hydrology
Merge branch 'master' into hydrology
fix and cleanup Fill operation
fix Fill operation in hydrology
Minor bug fix: rr should be used in a conditional.
Merge pull request #666 from wzjchen/minorbug

Minor bug fix in IDWInterpolation
change ArgWritable to convert to/from RasterData
Gave the ability to have zonal summary use cached results.

- Added a .cached method to DataSourceLike that caches the results
  of the elements on the local machine.
- Refactored zonal summary methods to take in cached results
  to be used on the full tile intersections.
Merge pull request #664 from Markko/hydrology

add fill operation to hydrology