use .pull-right to keep dropdowns aligned in example

BS3 commit 8cb1b766f8c3991fdc59140681378e733ea5c93a
align horizontal form label and input. remove lingering .nav-header

BS3 commits 14f688c7fc7fa6569d066320c62be02b17ca91dc,
e953c23019ca8abd14e29eb03290ec6bbf5fedd9