add config file for default view
get default view from config
add config instructions to readme
don't set the default view in the Manager
register package under laravel-breadcrumbs rather than breadcrumbs

NB: I've done this because the publish command doesn't respect the altered registered name (i've submitted a bug report for that)

Fixes #10
Change Bootstrap 3 to be the default template
Rename bootstrap template to bootstrap2
Big README update for v2.0