updated changelog

Author: jorijn

CHANGELOG.md

@@ -1,5 +1,11 @@
 # Changelog for Laravel Security Checker
 
+## v0.3.0 (2018-08-03)
+* updated to work on Laravel 5.5.x, 5.6.x and 5.7.x, thanks @jorgenb
+* dropped support for PHP 5.x
+* added Slack notifications on vulnerabilities, thanks @jorgenb
+* renamed LCS_EMAIL_WITHOUT_VULNERABILITIES TO LCS_NOTIFY_WITHOUT_VULNERABILITIES to reflect the Slack notification
+
 ## v0.2.2 (2017-07-23)
 * wrote tests to cover 100% of the package functionality
 
@@ -9,4 +15,4 @@
 
 ## v0.2.0 (2017-07-22)
 * added configuration option that won't email you when there are no vulnerabilities and it is enabled by default.
-* code improvements
+* code improvements