Update to Symfony 4.1 #149 (#160)

* updated to Symfony 4.1 #149
* updated to phpunit 7 #149
* downgrade ocramius/proxy-manager for PHP 7.1 compatibility #149
* fixed symfony deprecations #149
* replaced AdvancedUserInterface with custom user checker
* code sniffer fixes

symfony.lock

@@ -11,6 +11,9 @@
     "composer/semver": {
         "version": "1.4.2"
     },
+    "composer/xdebug-handler": {
+        "version": "1.1.0"
+    },
     "dama/doctrine-test-bundle": {
         "version": "4.0",
         "recipe": {
@@ -113,9 +116,6 @@
             "ref": "bb31a3bbec00a8fc8aa1c9fbf9b0ef9fc492f93d"
         }
     },
-    "gecko-packages/gecko-php-unit": {
-        "version": "v3.0"
-    },
     "jdorn/sql-formatter": {
         "version": "v1.2.17"
     },
@@ -125,6 +125,9 @@
     "myclabs/deep-copy": {
         "version": "1.7.0"
     },
+    "nikic/php-parser": {
+        "version": "v4.0.2"
+    },
     "ocramius/package-versions": {
         "version": "1.2.0"
     },
@@ -179,9 +182,6 @@
             "ref": "9d0927a518f631b4ae6508dac377b021761ff6d1"
         }
     },
-    "phpunit/phpunit-mock-objects": {
-        "version": "5.0.6"
-    },
     "psr/cache": {
         "version": "1.0.1"
     },
@@ -377,6 +377,9 @@
             "ref": "179470cb6492db92dffee208cfdb436f175c93b4"
         }
     },
+    "symfony/polyfill-ctype": {
+        "version": "v1.8.0"
+    },
     "symfony/polyfill-intl-icu": {
         "version": "v1.6.0"
     },
@@ -404,9 +407,6 @@
             "ref": "cda8b550123383d25827705d05a42acf6819fe4e"
         }
     },
-    "symfony/security": {
-        "version": "v4.0.3"
-    },
     "symfony/security-bundle": {
         "version": "3.3",
         "recipe": {