PLT-2257 Reorganized System Console (#3003)

* Reorganized system console

* Fixed the names of some components

* Fixed timestamp for BrandImageSetting

* Fixed merge issues

* Updated push notification settings to match master branch

* Removed top level setting pages and moved enable Gitlab/LDAP settings onto their respective pages

* Re-added restrictDirectMessage setting to system console

* Re-added email connection test and fixed some margins

* Fixed ESLint errors

* Renamed Authentication > Onboarding to Authentication > Email in the system console

* Renamed Customization > Whitelabeling to Customization > Custom Branding in System Console

* Re-added EnableOpenServer to system console

webapp/components/admin_console/developer_settings.jsx

@@ -0,0 +1,83 @@
+// Copyright (c) 2015 Mattermost, Inc. All Rights Reserved.
+// See License.txt for license information.
+
+import React from 'react';
+
+import AdminSettings from './admin_settings.jsx';
+import BooleanSetting from './boolean_setting.jsx';
+import {FormattedMessage} from 'react-intl';
+import SettingsGroup from './settings_group.jsx';
+
+export default class DeveloperSettings extends AdminSettings {
+    constructor(props) {
+        super(props);
+
+        this.getConfigFromState = this.getConfigFromState.bind(this);
+
+        this.renderSettings = this.renderSettings.bind(this);
+
+        this.state = Object.assign(this.state, {
+            enableTesting: props.config.ServiceSettings.EnableTesting,
+            enableDeveloper: props.config.ServiceSettings.EnableDeveloper
+        });
+    }
+
+    getConfigFromState(config) {
+        config.ServiceSettings.EnableTesting = this.state.enableTesting;
+        config.ServiceSettings.EnableDeveloper = this.state.enableDeveloper;
+
+        return config;
+    }
+
+    renderTitle() {
+        return (
+            <h3>
+                <FormattedMessage
+                    id='admin.developer.title'
+                    defaultMessage='Developer Settings'
+                />
+            </h3>
+        );
+    }
+
+    renderSettings() {
+        return (
+            <SettingsGroup>
+                <BooleanSetting
+                    id='enableTesting'
+                    label={
+                        <FormattedMessage
+                            id='admin.service.testingTitle'
+                            defaultMessage='Enable Testing: '
+                        />
+                    }
+                    helpText={
+                        <FormattedMessage
+                            id='admin.service.testingDescription'
+                            defaultMessage='(Developer Option) When true, /loadtest slash command is enabled to load test accounts and test data. Changing this will require a server restart before taking effect.'
+                        />
+                    }
+                    value={this.state.enableTesting}
+                    onChange={this.handleChange}
+                />
+                <BooleanSetting
+                    id='enableDeveloper'
+                    label={
+                        <FormattedMessage
+                            id='admin.service.developerTitle'
+                            defaultMessage='Enable Developer Mode: '
+                        />
+                    }
+                    helpText={
+                        <FormattedMessage
+                            id='admin.service.developerDesc'
+                            defaultMessage='(Developer Option) When true, extra information around errors will be displayed in the UI.'
+                        />
+                    }
+                    value={this.state.enableDeveloper}
+                    onChange={this.handleChange}
+                />
+            </SettingsGroup>
+        );
+    }
+}