Add plumbing for PeerDAS supernodes (#5050, #5409, #5570, #5966) (#6216)

* Add plumbing for peerdas supernodes (#5050, #5409, #5570, #5966)
- add cli option `--subscribe-to-all-data-columns`
- add custody subnet count to ENR, only if PeerDAS is scheduled
- subscribe to data column topics, only if PeerDAS is scheduled

Co-authored-by: Jacob Kaufmann <jacobkaufmann18@gmail.com>

* Merge branch 'unstable' into das-supernode

* Update CLI docs.

* Merge branch 'unstable' into das-supernode

* Fix fork epoch comparison with `FAR_FUTURE_EPOCH`.

* Merge branch 'unstable' into das-supernode

* Hide `--subscribe-all-data-column-subnets` flag and update help.

* Fix docs only

* Merge branch 'unstable' into das-supernode

beacon_node/lighthouse_network/src/service/mod.rs

@@ -162,6 +162,7 @@ impl<E: EthSpec> Network<E> {
                 &config,
                 &ctx.enr_fork_id,
                 &log,
+                ctx.chain_spec,
             )?;
             // Construct the metadata
             let meta_data = utils::load_or_build_metadata(&config.network_dir, &log);