Fix P4.run_submit( P4::Spec )
Ruby 1.9 changed Array.flatten, so that it called 'to_ary'. This
caused problems for P4Ruby (with Ruby 1.9) and would cause
P4.run_submit, P4.run_shelve, etc to fail with:
`method_missing': undefined method `to_ary' for object of class P4::Spec (RuntimeError)
if it was passed a P4::Spec object as an argument.
P4::Spec now checks (in 'method_missing') if it's trying to run
'to_ary', and it raises 'NoMethodError' if it is.