Merge pull request #303 from RyanTG/master

accessibility - better alt tags for images
adding rubocop
rubocop fixes
more liberal line length for rubocop
rubocop compliance
rubocop compliance
Merge branch 'enhancements'
home page copy
rubocop compliance
Merge branch 'enhancements'
rubocop compliance
Merge branch 'enhancements'
merge branch 'master' of https://github.com/scottwainstock/pbm