Created cleanup functionality for syncthing (#6884)

* Add clean up for Simple File Versioning pt.1

created test

* Add clean up for Simple File Versioning pt.2

Passing the test

* stuck on how javascript communicates with backend

* Add trash clean up for Simple File Versioning

Add trash clean up functionality of to allow the user to delete backups
after specified amount of days.

* Fixed html and js style

* Refactored cleanup test cases

Refactored cleanup test cases to one file and deleted duplicated code.

* Added copyright to test file

* Refactor folder cleanout to utility function

* change utility function to package private

* refactored utility function; fixed build errors

* Updated copyright year.

* refactor test and logging

* refactor html and js

* revert style change in html

* reverted changes in html and some js

* checkout origin head version edit...html

* checkout upstream master and correct file

lib/versioner/trashcan_test.go

@@ -7,10 +7,7 @@
 package versioner
 
 import (
-	"context"
 	"io/ioutil"
-	"os"
-	"path/filepath"
 	"testing"
 	"time"
 
@@ -18,76 +15,6 @@ import (
 	"github.com/syncthing/syncthing/lib/fs"
 )
 
-func TestTrashcanCleanout(t *testing.T) {
-	// Verify that files older than the cutoff are removed, that files newer
-	// than the cutoff are *not* removed, and that empty directories are
-	// removed (best effort).
-
-	var testcases = []struct {
-		file         string
-		shouldRemove bool
-	}{
-		{"testdata/.stversions/file1", false},
-		{"testdata/.stversions/file2", true},
-		{"testdata/.stversions/keep1/file1", false},
-		{"testdata/.stversions/keep1/file2", false},
-		{"testdata/.stversions/keep2/file1", false},
-		{"testdata/.stversions/keep2/file2", true},
-		{"testdata/.stversions/keep3/keepsubdir/file1", false},
-		{"testdata/.stversions/remove/file1", true},
-		{"testdata/.stversions/remove/file2", true},
-		{"testdata/.stversions/remove/removesubdir/file1", true},
-	}
-
-	os.RemoveAll("testdata")
-	defer os.RemoveAll("testdata")
-
-	oldTime := time.Now().Add(-8 * 24 * time.Hour)
-	for _, tc := range testcases {
-		os.MkdirAll(filepath.Dir(tc.file), 0777)
-		if err := ioutil.WriteFile(tc.file, []byte("data"), 0644); err != nil {
-			t.Fatal(err)
-		}
-		if tc.shouldRemove {
-			if err := os.Chtimes(tc.file, oldTime, oldTime); err != nil {
-				t.Fatal(err)
-			}
-		}
-	}
-
-	cfg := config.FolderConfiguration{
-		FilesystemType: fs.FilesystemTypeBasic,
-		Path:           "testdata",
-		Versioning: config.VersioningConfiguration{
-			Params: map[string]string{
-				"cleanoutDays": "7",
-			},
-		},
-	}
-
-	versioner := newTrashcan(cfg).(*trashcan)
-	if err := versioner.Clean(context.Background()); err != nil {
-		t.Fatal(err)
-	}
-
-	for _, tc := range testcases {
-		_, err := os.Lstat(tc.file)
-		if tc.shouldRemove && !os.IsNotExist(err) {
-			t.Error(tc.file, "should have been removed")
-		} else if !tc.shouldRemove && err != nil {
-			t.Error(tc.file, "should not have been removed")
-		}
-	}
-
-	if _, err := os.Lstat("testdata/.stversions/keep3"); os.IsNotExist(err) {
-		t.Error("directory with non empty subdirs should not be removed")
-	}
-
-	if _, err := os.Lstat("testdata/.stversions/remove"); !os.IsNotExist(err) {
-		t.Error("empty directory should have been removed")
-	}
-}
-
 func TestTrashcanArchiveRestoreSwitcharoo(t *testing.T) {
 	// This tests that trashcan versioner restoration correctly archives existing file, because trashcan versioner
 	// files are untagged, archiving existing file to replace with a restored version technically should collide in