## Issue Addressed
Fixes#1509
## Proposed Changes
Exit the beacon node if the eth1 endpoint points to an invalid eth1 network. Check the network id before every eth1 cache update and display an error log if the network id has changed to an invalid one.
* Add logging on shutdown
* Replace tokio::spawn with handle.spawn
* Upgrade tokio
* Add a task executor
* Beacon chain tasks use task executor
* Validator client tasks use task executor
* Rename runtime_handle to executor
* Add duration histograms; minor fixes
* Cleanup
* Fix logs
* Fix tests
* Remove random file
* Get enr dependency instead of libp2p
* Address some review comments
* Libp2p takes a TaskExecutor
* Ugly fix libp2p tests
* Move TaskExecutor to own file
* Upgrade Dockerfile rust version
* Minor fixes
* Revert "Ugly fix libp2p tests"
This reverts commit 58d4bb690f52de28d893943b7504d2d0c6621429.
* Pretty fix libp2p tests
* Add spawn_without_exit; change Counter to Gauge
* Tidy
* Move log from RuntimeContext to TaskExecutor
* Fix errors
* Replace histogram with int_gauge for async tasks
* Fix todo
* Fix memory leak in test by exiting all spawned tasks at the end