Adding CHANGELOG.md.

Signed-off-by:Ivan Tcholakov <ivantcholakov@gmail.com>

Author: ivantcholakov

CHANGELOG.md

@@ -0,0 +1,15 @@
+# 1.4.3 - 07-JUN-2020
+
+- CHANGELOG.md file has been added.
+
+
+# 1.4.2 - 06-JUN-2020
+
+- New installation instructions have been prepared.
+
+
+# 1.4.1 - 06-JUN-2020
+
+- Initial Composer-managed package. Requirements: CodeIgniter 3.1.x, PHP >= 5.5.0, Composer enabled, PHP >= 6.1.6.
+- For supporting CodeIgniter 2.x and CodeIgniter 3.0.x a manual installation an an older versiosion of this
+  library is needed, see https://github.com/ivantcholakov/codeigniter-phpmailer/tree/1.3-stable