New class modeling moving obstacles in grid-worlds
Improve (optional) performance of add_trolls, new tests for MGridWorld
TEST: run_tests.py flag "--fast" to skip slow tests
TRIV: Live long 4-space indentation!
TEST: Mark jtlv_test() and other_test() as "slow" in syntaxcheck_test.py
New plot() for MGridWorld class
Improve use of "verbose" flag for synthesize() and reach_localfixpoint()
Make accessible troll variable name prefixes in MGridWorld
EXAMPLE: Workaround to adjust troll radii, until MGridWorld settles down
EXAMPLE: Switch default to nonbool for localmu_unreach_discrete sim script
Merge branch 'master' into trolled_gridworld_format

Conflicts:
	run_tests.py
Update for new expectations of arguments to NumPy.hstack()