Explicit settings support

[flyingmutant]

To have an ability to customuze e.g. checks or steps per-test, without altering global environment.

Spin-off of #35.

[mirandaconrado]

@flyingmutant I'm pretty interested in this as we have some tests that need tuning of the configuration (mainly to reduce the number of runs and usually have more steps in the state machine). I'd be happy to contribute this back. Do you have a design in mind (I saw your suggestion)?

[flyingmutant]

I think something like you've linked should be decent place to start:

• all top-level state should move to something like var globalEnv Env
• top-level Check will become globalEnv.Check(...).
• WithOptions (need to decide on a good name) will construct an Env that overrides stuff in globalEnv

If you'll send a PR, I'll try my best with reviewing but can't promise very quick turnaround right now.

[ashishnegi]

+1 for this

[flyingmutant]

There is a chance that 4391f11 will mostly obviate the need to specify settings explicitly.