Added PHP 7.3 support - updated Travis CI configuration

Author: michalbundyra

.travis.yml

@@ -1,5 +1,3 @@
-sudo: false
-
 language: php
 
 cache:
@@ -84,6 +82,18 @@ matrix:
       env:
         - DEPS=latest
         - TESTS_ZEND_DIAGNOSTICS_MEMCACHED_ENABLED=true
+    - php: 7.3
+      env:
+        - DEPS=lowest
+        - TESTS_ZEND_DIAGNOSTICS_MEMCACHED_ENABLED=true
+    - php: 7.3
+      env:
+        - DEPS=locked
+        - TESTS_ZEND_DIAGNOSTICS_MEMCACHED_ENABLED=true
+    - php: 7.3
+      env:
+        - DEPS=latest
+        - TESTS_ZEND_DIAGNOSTICS_MEMCACHED_ENABLED=true
 
 before_install:
   - if [[ $TEST_COVERAGE != 'true' ]]; then phpenv config-rm xdebug.ini || return 0 ; fi