always show search box in instance header; also line up instance header items
updated styling for new, more common, nothing-here-yet-messages
more whitespace around form on speaker/speech/section editing pages
replace admin-menu with user-menu in base.html header bar
a few more user-menu improvements
show login link on homepage
disable django-allauth messages on login and logout
styling for extra lead paragraphs in nothing-here-yet-messages
styles to match more compact speech editing form