Add browse page for pharma industry

Relates to https://www.pivotaltracker.com/story/show/67287128 and is the
other half of https://github.com/alphagov/panopticon/pull/141.
Merge pull request #544 from alphagov/add-pharma-industry-browse-page

Add browse page for pharma industry

https://www.pivotaltracker.com/story/show/67287128