add support for graph-output

First version, really hackish, works-ish

Signed-off-by: Henrik Austad <haustad@cisco.com>
Place pair on same core

When testing inter-core semaphore synchronization, one also need to see
what the delay between 2 tasks are when they run on the same core. This
enables just that.

Signed-off-by: Henrik Austad <haustad@cisco.com>