Hide city field for non-administrators

Addresses #3485
Merge pull request #13 from ghing/3485-hide_city_field

Hide city field for non-administrators
Merge branch '7.x-1.x' into 3485-add_member_inline
Better UI/UX for inline adding of board term members

This took some fairly nasty hacking in
``hook_field_widget_WIDGET_TYPE_form_alter()`` to accomplish, but things
feel nicer now.

* Initially show the autocomplete field to select an existing member
* Replace "node" in microcopy with "Member"

Addresses #3485