Collect information about all of the currently executing go routines
within a process by handling SIGUSR1. SIGUSR1 will not terminate the
process.

Change-Id: Ide5a26a8f1ee9bae93d3c6ba4b0b178661cbfd6c
Signed-off-by: Saad Karim <skarim@us.ibm.com>
Signed-off-by: Matthew Sykes <sykesmat@us.ibm.com>