v0.4.3

• Fix: Do not take start of body into account when checking maximum header size
  (#88 by @nopolabs)
• Fix: Remove data listener if HeaderParser emits an error
  (#83 by @nick4fake)
• First class support for PHP 5.3 through PHP 7 and HHVM
  (#101 and #102 by @clue, #66 by @WyriHaximus)
• Improve test suite by adding PHPUnit to require-dev,
  improving forward compatibility with newer PHPUnit versions
  and replacing unneeded test stubs
  (#92 and #93 by @nopolabs, #100 by @legionth)