update gulp to 4+

Author: viscosho

gulpfile.js

@@ -13,7 +13,7 @@ gulp.task('default', function() {
 	console.log('gulp wordpress-lang to compile the to-team.pot, to-team-en_EN.po and to-team-en_EN.mo');
 });
 
-gulp.task('wordpress-pot', function() {
+gulp.task('wordpress-pot', function(done) {
 	return gulp.src('**/*.php')
 		.pipe(sort())
 		.pipe(wppot({
@@ -22,10 +22,11 @@ gulp.task('wordpress-pot', function() {
 			bugReport: 'https://bitbucket.org/feedmycode/to-team',
 			team: 'LightSpeed <webmaster@lsdev.biz>'
 		}))
-		.pipe(gulp.dest('languages/to-team.pot'))
+		.pipe(gulp.dest('languages/to-team.pot')),
+		done();
 });
 
-gulp.task('wordpress-po', function() {
+gulp.task('wordpress-po', function(done) {
 	return gulp.src('**/*.php')
 		.pipe(sort())
 		.pipe(wppot({
@@ -34,13 +35,17 @@ gulp.task('wordpress-po', function() {
 			bugReport: 'https://bitbucket.org/feedmycode/to-team',
 			team: 'LightSpeed <webmaster@lsdev.biz>'
 		}))
-		.pipe(gulp.dest('languages/to-team-en_EN.po'))
+		.pipe(gulp.dest('languages/to-team-en_EN.po')),
+		done();
 });
 
-gulp.task('wordpress-po-mo', ['wordpress-po'], function() {
+gulp.task('wordpress-po-mo', gulp.series( ['wordpress-po'], function(done) {
 	return gulp.src('languages/to-team-en_EN.po')
 		.pipe(gettext())
-		.pipe(gulp.dest('languages'))
-});
+		.pipe(gulp.dest('languages')),
+		done();
+}));
 
-gulp.task('wordpress-lang', (['wordpress-pot', 'wordpress-po-mo']));
+gulp.task('wordpress-lang', gulp.series( ['wordpress-pot', 'wordpress-po-mo'] , function(done) {
+	done();
+}));