fix(block_time): block time can no longer be less than pending block update time

[Trantorian1]

Pull Request type

• Bugfix

What is the current behavior?

Block time can be less than pending block update time (also known as tick time). This is an issue as it means only empty blocks will be produced.

Resolves: #277

What is the new behavior?

Forbids the node from starting as a sequencer if ever its block time is less than its tick time.

Does this introduce a breaking change?

No

[Mohiiit]

lgtm, minor doubts

[notlesh]

Left a couple nits/questions, but also wanted to ask if block time and bending block update time are documented anywhere. I don't see them in --help.

Tick time was also confusing to me while reading through the PR/issue, is that a user-facing term? If not, no big deal.

[Trantorian1]

Left a couple nits/questions, but also wanted to ask if block time and bending block update time are documented anywhere. I don't see them in --help.

Tick time was also confusing to me while reading through the PR/issue, is that a user-facing term? If not, no big deal.

Yep, this was pretty confusing to me too when I started work on this PR. I have added docs to all of this into the CLI. Hopefully this makes this part of the code a bit clearer.