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/text_setting.jsx

@@ -0,0 +1,83 @@
+// Copyright (c) 2016 Mattermost, Inc. All Rights Reserved.
+// See License.txt for license information.
+
+import React from 'react';
+
+import Setting from './setting.jsx';
+
+export default class TextSetting extends React.Component {
+    static get propTypes() {
+        return {
+            id: React.PropTypes.string.isRequired,
+            label: React.PropTypes.node.isRequired,
+            placeholder: React.PropTypes.string,
+            helpText: React.PropTypes.node,
+            value: React.PropTypes.oneOfType([
+                React.PropTypes.string,
+                React.PropTypes.number
+            ]).isRequired,
+            onChange: React.PropTypes.func.isRequired,
+            disabled: React.PropTypes.bool,
+            type: React.PropTypes.oneOf([
+                'input',
+                'textarea'
+            ])
+        };
+    }
+
+    static get defaultProps() {
+        return {
+            type: 'input'
+        };
+    }
+
+    constructor(props) {
+        super(props);
+
+        this.handleChange = this.handleChange.bind(this);
+    }
+
+    handleChange(e) {
+        this.props.onChange(this.props.id, e.target.value);
+    }
+
+    render() {
+        let input = null;
+        if (this.props.type === 'input') {
+            input = (
+                <input
+                    id={this.props.id}
+                    className='form-control'
+                    type='text'
+                    placeholder={this.props.placeholder}
+                    value={this.props.value}
+                    onChange={this.handleChange}
+                    disabled={this.props.disabled}
+                />
+            );
+        } else if (this.props.type === 'textarea') {
+            input = (
+                <textarea
+                    id={this.props.id}
+                    className='form-control'
+                    rows='5'
+                    maxLength='1024'
+                    placeholder={this.props.placeholder}
+                    value={this.props.value}
+                    onChange={this.handleChange}
+                    disabled={this.props.disabled}
+                />
+            );
+        }
+
+        return (
+            <Setting
+                label={this.props.label}
+                helpText={this.props.helpText}
+                inputId={this.props.id}
+            >
+                {input}
+            </Setting>
+        );
+    }
+}