Puppet-lint fixes
Merge pull request #327 from hundredacres/master

Puppet-lint fixes
Add proxy_read_timeout
Replaced params references with config.
Added 4 proxy parameters.
client_body_buffer_size
proxy_connect_timeout
proxy_read_timeout
proxy_send_timeout

And reference these variabels in the template.
Add super_user option to be able to launch nginx as unprivileged user without complains.