add upstart support to nginx::source
recipe inserts daemon off into main conf, remove it from upstart.conf
add another attribute to accurately control upstart fore/background behavior
fix minor formatting issue in upstart template
Merge remote-tracking branch 'upstream/master' into COOK-2622
remove recipe defaults (use attribute defaults), fix README snafu, convert unless/nil to if
whitespace pedantry
Merge pull request #99 from brandonmartin/COOK-2622

COOK-2622 - nginx: add upstart support