Developer improvements, PhpCs, PhpUnit #42 (#43)

* improved dev fixtures with more diversity, more data, better testcases, user avatars #42
* added customer stats to dashboard, fixed column length for 3 widgets #42
* fixed empty alias - display empty message for new user #42
* unified-ui for "new" toolbar icon #42
* use kimai2_ as database prefix #42
* added customer stats to dashboard, fixed column length for 3 widgets #42
* fix long project/customer names in "currently active" navbar flyout" #42
* added services config for dev environment #42
* added command to run unit tests #42
* added command to run integration tests #42
* added command to run code sniffer #42
* added phpcs and phpunit to composer #42
* created tests directory #42
* fixed code sniffer warnings #42
* added function to switch result type from Pagerfanta to QueryBuilder #42
* dramatically reduced database calls by using custom joined query #42
* added command to install kimai dependencies #42
* added dev:reset command #42

composer.json

@@ -44,7 +44,9 @@
     },
     "require-dev": {
         "sensio/generator-bundle": "~3.0",
-        "symfony/phpunit-bridge": "^3.0"
+        "symfony/phpunit-bridge": "^3.0",
+        "squizlabs/php_codesniffer": "3.*",
+        "phpunit/phpunit": "^6"
     },
     "scripts": {
         "post-install-cmd": [