Better configurations

[kianenigma]

At the moment, flite allows you to configure these things:

https://github.com/kianenigma/flite/blob/c0316b4974069d92fd11ba98b5f0c618495502a2/flite/src/lib.rs#L216-L223

And in return it will give you a sane implementation of

• balances
• timestamp
• aura

We should think about what other configurations are reasonable for flite.

A great one would be block-time, related to #2. We currently may have a 12s or 6s parachain. With elastic scaling, we could even have more. FLITE can provide a very easy configuration for this:

pub enum ParaBlockTime {
    12s,
    6s,
    MultiCore(n)
}