adding support to 'line numbers' settings (#116)

* adding support to 'line numbers' settings

* Update Settings.js

components/Carbon.js

@@ -72,7 +72,7 @@ class Carbon extends React.Component {
     const config = { ...DEFAULT_SETTINGS, ...this.props.config }
 
     const options = {
-      lineNumbers: false,
+      lineNumbers: config.lineNumbers,
       mode: this.state.language || 'plaintext',
       theme: config.theme,
       scrollBarStyle: null,

components/Settings.js

@@ -51,6 +51,11 @@ class Settings extends React.Component {
             enabled={this.props.enabled.widthAdjustment}
             onChange={this.props.onChange.bind(null, 'widthAdjustment')}
           />
+          <Toggle
+            label="Line Numbers"
+            enabled={this.props.enabled.lineNumbers}
+            onChange={this.props.onChange.bind(null, 'lineNumbers')}
+          />
           <Slider
             label="Padding (vertical)"
             initialValue={16}

pages/editor.js

@@ -49,6 +49,7 @@ class Editor extends React.Component {
       dropShadow: true,
       windowControls: true,
       widthAdjustment: true,
+      lineNumbers: false,
       paddingVertical: '48px',
       paddingHorizontal: '32px',
       uploading: false,