Update Travis to include various SS versions and PHP 7.3 and use PSR-12

.travis.yml

@@ -7,13 +7,15 @@ env:
 matrix:
   include:
     - php: 5.6
-      env: DB=MYSQL PHPCS_TEST=1 PHPUNIT_TEST=1
+      env: DB=MYSQL RECIPE_VERSION=1.0.x-dev PHPCS_TEST=1 PHPUNIT_TEST=1
     - php: 7.0
-      env: DB=MYSQL PHPUNIT_TEST=1
+      env: DB=MYSQL RECIPE_VERSION=1.1.x-dev PHPUNIT_TEST=1
     - php: 7.1
-      env: DB=MYSQL PHPUNIT_COVERAGE_TEST=1
+      env: DB=MYSQL RECIPE_VERSION=4.2.x-dev PHPUNIT_COVERAGE_TEST=1
     - php: 7.2
-      env: DB=MYSQL PHPUNIT_TEST=1
+      env: DB=PGSQL RECIPE_VERSION=4.3.x-dev PHPUNIT_TEST=1
+    - php: 7.3
+      env: DB=MYSQL RECIPE_VERSION=4.x-dev PHPUNIT_TEST=1
 
 before_script:
   # Init PHP
@@ -23,7 +25,8 @@ before_script:
 
   # Install composer dependencies
   - composer validate
-  - composer require --no-update silverstripe/recipe-cms:1.0.x-dev
+  - composer require --no-update silverstripe/recipe-cms:"$RECIPE_VERSION"
+  - if [[ $DB == PGSQL ]]; then composer require --no-update silverstripe/postgresql:2.2.x-dev; fi
   - composer install --prefer-dist --no-interaction --no-progress --no-suggest --optimize-autoloader --verbose --profile
 
 script:

phpcs.xml.dist

@@ -2,7 +2,7 @@
 <ruleset name="SilverStripe">
     <description>CodeSniffer ruleset for SilverStripe coding conventions.</description>
 
-    <rule ref="PSR2" >
+    <rule ref="PSR12" >
         <!-- Current exclusions -->
         <exclude name="PSR1.Methods.CamelCapsMethodName" />
     </rule>