allow to configure CometBFT genesis consensus params

[tzemanovic]

Allow to configure the cometBFT genesis consensus params from our genesis config, i.e.:

pub struct Params {
    /// Block size parameters
    pub block: Option<block::Size>,

    /// Evidence parameters
    pub evidence: Option<evidence::Params>,

    /// Validator parameters
    pub validator: Option<ValidatorParams>,

    /// Version parameters
    pub version: Option<VersionParams>,
}

We don't need the evidence params as outdated evidence is being handled in the ledger.

Depends on #711

[adrianbrink]

Needs to be coordinated with #2122

[sug0]

the only thing we cared about from this issue was the ability to configure cometbft block sizes, which was implemented here: #2187