Reorganise tests to match modern rails test layout
Highlight erroneous fields by adding a class to them The default rails scheme for highlighting errors is to wrap the field in a div, but that changes the structure of the page and can change the meaning of CSS rules applied to the fields. As an alternative we now apply a class to the fields, and use that in the CSS to apply a highlight.
Simplify browse routes and make routes more consistent This gets rid of the /browse/ prefix and uses /history consistently for all routes that show a list of changesets.