test against php 7.3 and 7.4

Author: sergiy-petrov

.travis.yml

@@ -4,6 +4,8 @@ php:
   - 7.0
   - 7.1
   - 7.2
+  - 7.3
+  - 7.4
 
 notifications:
   email: false
@@ -17,4 +19,4 @@ before_script:
 
 # Run PHPs run-tests.php 
 script:
-    - ./travis/run-test.sh
+    - ./travis/run-test.sh