Process: Added test cases for testing Ctrl+C and process groups.

Two new tests were added to testProcess:
 * Test 9 is constructed of the root test process, a child process,
   and a grandchild process.  The grandchild ignores all Ctrl+C signals
   and then sleeps.  The child runs the grandchild normally.  The root
   process runs the child in a new process group, sends it a Ctrl+C
   signal, and then lets the process expire to prove that the child was
   blocked waiting for the uninterruptable grandchild to die.
 * Test 10 is constructed of the root test process, a child process,
   and a grandchild process.  The grandchild sleeps and processes
   signals normally.  The child runs the grandchild in a new process
   group.  The root process runs the child in a new process group as
   well, sends it a Ctrl+C, and then verifies that: (1) the child does
   indeed terminate with an interrupt signal, (2) the child did not
   expire, proving that it retransmitted the signal to the sleeping
   grandchild before waiting for the grandchild to terminate.

Change-Id: Iba5bee546a82eb61a41d4194341e9382a00279d4