cgo: added ability to disable closing

A do_close flag added to the Wrap* functions makes the wrapper
use or ignore the provided go objects' Close() method.
cgo: added ability to disable closing

A do_close flag added to the Wrap* functions makes the wrapper
use or ignore the provided go objects' Close() method.

Update #19 & #21.
Merge branch 'cgo_disable_close' of https://github.com/cookieo9/go-misc into cgo_disable_close
cgo: updated test-script
Merge pull request #22 from cookieo9/cgo_disable_close

cgo: control wrapper's close behavior