Update changelog, package version.

CHANGELOG.md

+## [1.3.0]
+* Image printing method has been improved
+* Using ESC * command to print images instead of outdated GS v 0
+* Added print image Flutter example
+
+
 ## [1.2.0]
-* printing images (beta)
+* Printing images (beta)
   
 
 ## [1.1.3]
 * printCodeTable bug fixed
-* updated test print example 
+* Updated test print example 
 
 
 ## [1.1.2]

pubspec.yaml

 name: esc_pos_printer
 description: The library allows to print receipts using a ESC/POS (usually thermal) network printer. It can be used in Flutter or Dart projects. In Flutter, both Android and iOS are supported.
-version: 1.2.0
+version: 1.3.0
 author: Andrey Ushakov <flutter@tablemi.com>
 homepage: https://github.com/andrey-ushakov/esc_pos_printer