Merge branch 'release/0.16'
Downgrade rubygems to 2.1.11

Rubygems 2.2.0 appears to have dropped support for ruby 1.8.7 - the
immediate problem for us is that there are errors in building the
charlock_holmes gem.
Use direct asset references in attachment HTML view.

This will be cached, so we don't want to use versioned asset references.
Fixing more typos
Fix typo
Merge branch 'hotfix/0.16.0.1' into wdtk

Conflicts:
    app/views/request/_view_html_stylesheet.html.erb