add test case 7 that does nothing but associate and waits for heartbeat

[warrenc5]

I have added a test case 7 that does nothing but associate and wait for heartbeat

warrenc5@c826fa3

This is to assist in testing the issue described

warrenc5#1

And

https://sourceforge.net/p/lksctp/mailman/lksctp-developers/thread/48AB4D61.8010204%40student.uibk.ac.at/#msg20142277