Errors in RegressionExErrors

2. needs mw in the list [~swc,rhc,off,mw]

3. should not exist, as "dc" achieves ~rhc.

6. should not exist (even if 3 were there as there is no need to
   deliver mail)

7. should not have "rhc" negated

8 should not exist as the robot can't be in "off" and "cs"
