NEW: Simplify test runs.

.travis.yml

@@ -19,19 +19,15 @@ env:
 matrix:
   include:
     - php: 5.6
-      env: DB=PGSQL PHPUNIT_TEST=1
-    - php: 5.6
-      env: DB=SQLITE PHPUNIT_TEST=1
-    - php: 5.6
-      env: DB=MYSQL PDO=1 PHPUNIT_TEST=1 PHPCS_TEST=1
-    - php: 5.6
-      env: DB=MYSQL BEHAT_TEST=1
-    - php: 5.6
-      env: NPM_TEST=1
+      env: DB=MYSQL PHPUNIT_TEST=1 PHPCS_TEST=1
     - php: 7.0
-      env: DB=MYSQL PHPUNIT_TEST=1
+      env: DB=PGSQL PHPUNIT_TEST=1
     - php: 7.1.2
       env: DB=MYSQL PDO=1 PHPUNIT_TEST=1
+    - php: 7.0
+      env: DB=MYSQL BEHAT_TEST=1
+    - php: 7.0
+      env: NPM_TEST=1
 
 before_script:
  - "if [ \"$PHPCS_TEST\" = \"1\" ]; then pyrus install pear/PHP_CodeSniffer; fi"