Bump minimum PHP version to 7.x on Travis

Author: sagikazarmark

.travis.yml

@@ -7,22 +7,25 @@ cache:
         - $HOME/.composer/cache/files
 
 php:
-    - 5.5
+    - 7.0
+    - 7.1
+    - 7.2
+    - 7.3
 
 env:
     - SUITE="curl" PACKAGE="php-http/curl-client:dev-master zendframework/zend-diactoros"
     - SUITE="Socket" PACKAGE="php-http/socket-client:dev-master php-http/client-common"
-    - SUITE="Guzzle5" PACKAGE="php-http/guzzle5-adapter:dev-master"
     - SUITE="Guzzle6" PACKAGE="php-http/guzzle6-adapter:dev-master"
     - SUITE="React" PACKAGE="php-http/react-adapter:dev-master"
     - SUITE="Buzz" PACKAGE="php-http/buzz-adapter:dev-master"
-    - SUITE="CakePHP" PACKAGE="php-http/buzz-adapter:dev-master"
-    - SUITE="Zend" PACKAGE="php-http/buzz-adapter:dev-master"
+    - SUITE="CakePHP" PACKAGE="php-http/cakephp-adapter:dev-master"
+    - SUITE="Zend" PACKAGE="php-http/zend-adapter:dev-master"
+    - SUITE="Artax" PACKAGE="php-http/artax-adapter:dev-master"
 
 matrix:
     include:
-        - php: 7.0
-          env: SUITE="Artax" PACKAGE="php-http/artax-adapter:dev-master"
+        - php: 5.5
+          env: SUITE="Guzzle5" PACKAGE="php-http/guzzle5-adapter:dev-master"
     allow_failures:
         - env: SUITE="Socket" PACKAGE="php-http/socket-client:dev-master php-http/client-common"