ENH: Implement RollingBallSubtractBackground filter

Change-Id: I532113fb3be2b4b30bd60d4f51737f88bb55a91c

STYLE: Remove unused commented-out code

Change-Id: Ib9814d89e841faca47ec4ed8cae3ad274ff2f75d

STYLE: Rename RollingBallStructuringElement to GrayscaleBallStructuringElement

Change-Id: Ifa6c6adfea10fd212ac5c1b2ade6fc2c60afd593

COMP: Fix linking issues in Windows

Change-Id: Ieb3935e968b15dbd7975000c0ed5ca4f4fdb7752

COMP: Fix up the CMake tests and move the images to Midas server

Change-Id: I89637852b601f2a316a049243e82a4bd3a5a0800

COMP: Change main definition since VS linker has bug

Change-Id: I3d2b39da5219e26716f484c885e8a7bfe7ebedf8

ENH: Add support for anistropic ball and differing ball and neighborhood sizes

Change-Id: I484a7da35dd1419ce310cb3dc785f4376c0455c1

ENH: Add support for anistropic ball to SubtractBackgroundImageFilter

Change-Id: I3c79a1aafd95ab29ef834d278789022a9d7ae983

ENH: Minor style issues

STYLE: typedef iterators locally instead of publicly

STYLE: Add minor comment about static_cast

BUG: Fix accidental shadowing of RadiusType

BUG: Update itk-module.cmake to indicate the correct dependencies

ENH: Remove most bounds checking via ImageFacesBoundaryCalculator