refactor: Remove utils package (#397)

- RELATED ISSUE(S):
Resolves #396

- DESCRIPTION:
Remove the utils package to avoid import dependencies between multiple packages. Devs are ready to have a little code duplication as a trade off.

utils/cid.go → core/cid.go

@@ -8,14 +8,14 @@
 // by the Apache License, Version 2.0, included in the file
 // licenses/APL.txt.
 
-package utils
+package core
 
 import (
 	"github.com/ipfs/go-cid"
 	mh "github.com/multiformats/go-multihash"
 )
 
-func NewCidV1(data []byte) (cid.Cid, error) {
+func NewCidV1_SHA2_256(data []byte) (cid.Cid, error) {
 	pref := cid.Prefix{
 		Version:  1,
 		Codec:    cid.Raw,

db/collection.go

@@ -22,7 +22,6 @@ import (
 	"github.com/sourcenetwork/defradb/db/base"
 	"github.com/sourcenetwork/defradb/logging"
 	"github.com/sourcenetwork/defradb/merkle/crdt"
-	"github.com/sourcenetwork/defradb/utils"
 
 	"errors"
 
@@ -160,7 +159,7 @@ func (db *db) CreateCollection(
 	}
 
 	// add a reference to this DB by desc hash
-	cid, err := utils.NewCidV1(buf)
+	cid, err := core.NewCidV1_SHA2_256(buf)
 	if err != nil {
 		return nil, err
 	}
@@ -204,7 +203,7 @@ func (db *db) GetCollectionByName(ctx context.Context, name string) (client.Coll
 	}
 
 	// add a reference to this DB by desc hash
-	cid, err := utils.NewCidV1(buf)
+	cid, err := core.NewCidV1_SHA2_256(buf)
 	if err != nil {
 		return nil, err
 	}