POS: Document default era length

[DylanVerstraete]

First we need to decide on a default Era duration for devnet and testnet

For example:

• Polkadot: Era (1 day), Epoch (4 hours)
• Kusama: Era (6 hours), Epoch (1hour)

It looks like the epoch duration is always the amount of hours in one Era / 6

[LeeSmet]

Epoch and session duration are customizable, and an era is expressed as some configurable amount of sessions

[DylanVerstraete]

I suggest we use following values:

• devnet: Era (1 hour), Epoch (10 minutes)
• testnet: Era (1 day), Epoch (4 hours)

[robvanmieghem]

what are the defaults?

[DylanVerstraete]

what are the defaults?

There are no defaults

[robvanmieghem]

@DylanVerstraete we have specific session lengths now, no? So what are the era lengths now(--dev, devnet, testnet) ?

[DylanVerstraete]

See: https://github.com/threefoldtech/tfchain/commit/3cbba39345587a07a3b28df3d5d0fe03b9479e17 is how we configure these values