Fixed VarDumpOptimizer support variable-length arguments, compatible for userland PHP 'var_dump' function.

Signed-off-by: Rack Lin <racklin@gmail.com>
Merge pull request #90 from racklin/bugfix/vardump

Fixed VarDumpOptimizer support variable-length arguments, compatible for...
Update README.md
Merge remote-tracking branch 'upstream/master'