Comply with Golang semantic import versioning (#630)

* Code: compatible with semantic import versioning

* Tools & Docs: compatible with semantic import versioning

* Clean go.mod & go.sum

pkg/filesystem/path_test.go

@@ -1,11 +1,12 @@
 package filesystem
 
 import (
+	"testing"
+
 	"github.com/DATA-DOG/go-sqlmock"
-	model "github.com/HFO4/cloudreve/models"
+	model "github.com/cloudreve/Cloudreve/v3/models"
 	"github.com/jinzhu/gorm"
 	"github.com/stretchr/testify/assert"
-	"testing"
 )
 
 func TestFileSystem_IsFileExist(t *testing.T) {