Log Message:
Update ruby-raindrops to 0.16.0.

=== raindrops 0.16.0 - minor fixes and workarounds / 2016-02-29 12:36 UTC

  There's mainly a fix/workaround for Ruby 2.3 now returning
  locale-aware strings for File.readlink and our test suite
  using strange paths allowed by *nix.

      https://bugs.ruby-lang.org/issues/12034

  tcp_listener_stats won't return "true" object placeholders
  if stats are configured for a non-existent listener.

  There are also minor optimizations for Ruby 2.2+ (at the expense
  of 2.1 and earlier).

  And the usual round of minor tweaks and doc updates.

  10 changes since v0.15.0:
        gemspec: avoid circular dependency on unicorn
        remove optimizations which made sense for older rubies
        linux: workaround Ruby 2.3 change
        linux: remove Pathname stdlib dependency
        add .gitattributes for Ruby method detection
        middleware: minor bytecode size reduction
        doc: update URLs and references
        README: remove indentation from URLs in RDoc
        linux: tcp_listener_stats drops "true" placeholders
        build: use '--local' domain for dev gem install