allow to login with email instead of nick as well + tests
start of making nickname optional
fix typo breaking invitation
make search work without nickname usage
more user display changes
user display changes in model and mailer
small model change
make user creation possible again
show user name with use_nick is false
beautify map invocations of users
fallback for when nick is nil
fix new user form
Merge branch 'master' into allow-no-nickname

Conflicts:
	app/views/foodcoop/users/_users.html.haml
remove unused memberships controller/view
remove unused autocomplete templates
remove unused layout
clearer login field name
use abbr instead of acronym for heading helper
workaround for integration test problem
allow large product lists in member order