add jump test, jumps not supported

A test of the jump operation has been added.  The test fails because the
current CPU does not support the jump opcode.
add missing and6 wire in control.v

The wire declaration for and6 was missing in the control.v module and
there were no errors.  Strange.  Add the missing and6 wire.
and4 same as and1 in control.v?

Found duplicate opcode signals, and1 and and4, in control.v.  It is
certainly a strange occurrence and it is unclear why this happened.
Remove and4 and replace it with and1.
simplify control.v using opcode names and a case statement

Previously, control.v parsed the opcode in to variables named: and1,
and2, and3, etc.  These names were obscure and did not describe what
their purpose is.  Rename these variables to their opcode names.

Also, simplify by removing the tedious bit parsing ~(oc[1]) and use a
case statement instead.
add jump opcode, not working yet

The jump opcode has been added in control.v but it is not working yet
because support still needs to be added to the rest of the system.