= Improvements

* The indifferent_params plugin is now optimized when using Rack 2,
  using Rack 2's query_parser API, and it no longer needs to do a
  deep copy of the params.

* The Content-Type and Content-Length headers are no longer added
  for 1xx, 204, 205, and 304 responses.

* The assets_paths method in the assets plugin now works
  correctly when subresource integrity is enabled.

* The asset paths are now escaped in tags by the assets and
  assets_preloading plugins.  While it's unlikely a developer
  would use an asset path that requires escaping, that case is
  now handled correctly.

* The h plugin no longer calls Rack::Utils.escape_html, instead
  implementing it's own html escaping.

* The assets plugin now uses the h plugin, instead of calling
  Rack::Utils.escape_html.

= Backwards Compatibility

* The h plugin's html escaping no longer escapes "/", which is
  a behavior change if you are using any recent version of rack.
  The security arguments made to escape "/" could be applied to
  many other characters, so if you want to escape "/", you should
  probably use a separate method that escapes all \W characters.
