Move Import Jobs and Reports under the repository menu to allow more room for the advanced search
Port the public advanced search behaviour to the staff frontend
Allow advance search field rows to be added and removed
Make addition of advanced search button to the search input comply with the proper bootstrap input-append DOM structure

Also add I18n'd titles to the search buttons in the navbar.
Fix staff advanced search when more than two queries
Fix bug in public advanced search where exception is raised when building the advanced_query when more than 2 fields are provided.
Introduce staff_field_query schema to override the values listed for the field enum in the staff interface. Both the field_query (public interface) and staff_field_query (staff interface) now refer to their own dynamic enum when populating the field lists
Introduce Selenium tests for the advanced search interface.

Use SecureRandom when generating unique strings for test data as time and processid was not always unique.

When checking if an element is not present, if it is in the DOM it should be hidden.
Move FrontendEnumSource into common so it can be shared with both the staff and public Rails apps; Fix an exception in the public app where it had no enum_source specified
Make changes after review:
 - rename frontend_enum_source.rb to client_enum_source.rb
 - refactor advanced query building logic into a common class so can be shared between public and staff controllers
 - remove silly whitespace
 - increment migration script number to 32 after rebase
Merge pull request #770 from hudmol/staff-advanced-search

Introduce advanced search to staff interface