add env_vars, sys_vars attributes to strategy returned by load_aut_xml

because it is basic information deduced by the loader and fundamental for expanding the contracted strategy to a strategy on the game graph (that is a deterministic game graph, unless the strategy has some redundancy that allows the system more than one winning reactions at certain points in the game).

Motivation was unit testing.
update gr1c test
bugfix in machines.random_run
replace set(iterable).pop() with next(iter(utterable))

to avoid unnecessary creation of a set.
print moves during random run of a transducer
update call to random_run in gr1 example
catch a strategy with no initial states and raise and exception