add file, support 500, 404 HTTP status
Merge branch 'master' of github.com:piecioshka/http-codes

* 'master' of github.com:piecioshka/http-codes:
  add default values
  delete text
  delete unused code from each case, print created header
  new HTTP codes supported
  short definitions
  add code blocks
  title upper
  add some docs
  rename response_code.php to index.php
  Initial commit
  add simple message for newbie
  delete files, replace them single file with big switch, use RFC