Update dkan_forms.slugify.js

Fixing a typo with slugify edit.
nuams/dkan#24 fix content type module name
Issue #16 Fixing group link
Merge pull request #13 from nuams/dkan_dataset_conten_type_display_name

nuams/dkan#24 fix content type module name
Merge pull request #14 from nuams/request-membership-link-to-group

Issue #16 Fixing group link
Adding updated js to fix issue with slugify