app-v1.5.6

• upgrade app version
• add some packages
• separate app file out main file
• update deprecated code in app_button.dart
• add restart dialog when user change language
• remove scroll animation when enter chat with someone
• make chat list start from last message like WhatsApp App
• add link preview when send URL in chat and make it clickable
• edit chat_bubbles package bubble_normal_image.dart file to show floating action button to save image if user is receiver
• add download received images on Gallery feature when open it
• add loading dialog until the image is sent or saved
• add some extensions on String ( isContainsLink & isNullOrEmpty )
• add custom message bar widget
• add custom link previewer widget
• make some packages locally