Upgrade to v5 schema

Now uses:
* ipld direct_by_leaf StateDB for basic queries
* trie_by_cid StateDB for trie slice and proof queries

Also:
* vulcanize => cerc refactor
* Backend method to close dbs
* state tests are in multiple packages, to allow separate ginkgo suites
* removes gap-filler module
* integration tests and github workflows
* run stack-orchestrator for testnet
* fix various issues with tests, hardhat server, dockerfile
* fix cmd flags / env vars
* fix flaky tests and clean up code
* remove unused code, scripts
* remove outdated docs
* update version

cmd/version.go

@@ -16,19 +16,17 @@
 package cmd
 
 import (
-	"github.com/cerc-io/ipld-eth-server/v4/pkg/log"
+	"github.com/cerc-io/ipld-eth-server/v5/pkg/log"
 	"github.com/spf13/cobra"
 
-	v "github.com/cerc-io/ipld-eth-server/v4/version"
+	v "github.com/cerc-io/ipld-eth-server/v5/version"
 )
 
 // versionCmd represents the version command
 var versionCmd = &cobra.Command{
 	Use:   "version",
 	Short: "Prints the version of ipld-eth-server",
-	Long: `Use this command to fetch the version of ipld-eth-server
-
-Usage: ./ipld-eth-server version`,
+	Long:  `Use this command to fetch the version of ipld-eth-server`,
 	Run: func(cmd *cobra.Command, args []string) {
 		subCommand = cmd.CalledAs()
 		logWithCommand = *log.WithField("SubCommand", subCommand)