Allow directory type selection in the delegated authentication directory in EMBCWD plugin

Currently there is no drop down to select the type of directory you'd like to integrate delegated authentication LDAP with in the Admin UI Plugin:

https://skitch.com/shihabske/rk4gm/configure-ldap-user-directory-jdog-jira-team-dogfood

Crowd does offer this option, and also pre-populates fields based on the selected directory type:

https://skitch.com/shihabske/rk4gf/configuring-a-delegated-authentication-directory-crowd-2.1-atlassian-documentation-confluence

The UI Plugin does implement a similar feature, but only for full LDAP directories. Perhaps we can borrow or share some of that code to implement this.