Update SimpleFilters

This update to SimpleFilters updates the documentation strings
presented in the help section, and updates the json to the current
version of SimpleITK in Slicer.

b27cdf6 Remove statistics only filters
148d863 Update help and acknowledgment text
bcdabde Fix json syntax issue StatisticsImageFilter
c62f9a8 Removing Filters which produce labelmaps as outputs
77fb3ac SimpleITK cd897256 Filter descriptions (reduced)
85d1ab2 Add utility script to generate Wiki table of filter