unicorn 5.5.2

Thanks to Terry Scheingeld, we now workaround a Ruby bug
and can now run with taint checks enabled:
<https://bugs.ruby-lang.org/issues/14485>
<https://bogomips.org/unicorn-public/CABg1sXrvGv9G6CDQxePDUqTe6N-5UpLXm7eG3YQO=dda-Cgg7A@mail.gmail.com/>

There's also a few documentation updates and building packages
from source is easier since pandoc is no longer a dependency
(and I can no longer afford the bandwidth or space to install
it).

Eric Wong (7):
      test/benchmark/ddstream: demo for slowly reading clients
      test/benchmark/readinput: demo for slowly uploading clients
      test/benchmark/uconnect: test for accept loop speed
      examples/unicorn@.service: note the NonBlocking flag
      Merge remote-tracking branch 'origin/ts/tmpio'
      test_util: get rid of some unused variables in tests
      doc: replace pandoc-"Markdown" with real manpages

Terry Scheingeld (1):
      tmpio: workaround File#path being tainted on unlink