easy exit for editing or supplying custom local_vars.yml file.

[jvonau]

1. Move local_vars.yml selection to Position "A"
2. Folded the dependency installs into local_vars selection.
3. Added easy back out exit point for nervous end-user: 'e' in local_vars_selector.
4. Created exit_for_custom_vars function for common use
5. Added easy exit point for end user to supply custom local_vars.yml file: '0' in local_vars_selector

Basic functionality with iiab_admin_user_install: with both True and False confirmed, prompted for password changes when needed.