Stop allowing incompatible options at runtime

[DWalker487]

Currently we can do e.g.

pyHepGrid run runcards/runcard.py -Dk

where asking to kill runs when submitting will be ignored but not throw an error.
IMO the best behaviour is to make this error our. The fix would need to be an update to option handling in argument_parser.py to disallow incompatible args at the same time.

Similarly when two allowed options are selected, such as

pyHepGrid man runcards/runcard.py -D -s -p

only one will be run (but there's no rhyme or reason as to which one it will be. This is controlled by the order of precedence/if statements in main_routines.py. IMO an error should also be thrown in this case as well for consistency.

[DWalker487]

See #23, commit 72150fe where I've removed interdependences. Seems to run ok.