Use ActiveAdmin.application.default_namespace so that activeadmin-sortable will work with applications that do no use the default namespace
Use resource_path for sort url to make sorting work with different namespaces and activeadmin resources that belong to another
Merge pull request #1 from anark/master

Use with any activeadmin namespace not just the default
merged from initial repo
added styles file; added generators to add require/import strings in js and css files
used single ajax request to save all sort changes(was in prev commit, but I broke it with last merge from original repo), added few styles for handler