PhatDB: DB representation as string instead of hash

+ Gob serialization appears to be non-deterministic
+ DB string is human readable
+ If we want a more concise format, we can just hash the representation
Fuzz testing: Resume nodes + wait + fail if state is not equal
make RunVR explicitly wait on the command it creates to commit (e.g. if some other factor makes that command commit, RunVR will still get notified)
Merge branch 'master' into fuzz_testing

Conflicts:
	fuzz_testing/test_master.go