[GREEN] implements Notification component

assets/js/components/Notification.jsx

+import React from 'react';
+import { Segment, Image, Button, Grid } from 'semantic-ui-react';
+
+const defaultThumbnail = 'https://semantic-ui.com/images/wireframe/square-image.png';
+
+export default class Notification extends React.Component {
+    
+  static propTypes = {
+    thumbnail: React.PropTypes.string,
+    text: React.PropTypes.string.isRequired,
+  };
+  
+  constructor(props) {
+    super(props);
+  };
+
+  render() {
+    return(
+        <Segment>
+            <Grid columns={3}>
+                <Grid.Row>
+                    <Grid.Column floated="left" width={2}>
+                        <Image 
+                            src={this.props.thumbnail ? this.props.thumbnail : defaultThumbnail} 
+                            size="tiny"
+                        />
+                    </Grid.Column>
+                    <Grid.Column width={12}>
+                        <p>{this.props.text}</p>
+                    </Grid.Column>
+                    <Grid.Column floated="right" width={2}>
+                        <Button primary>Dismiss</Button>
+                    </Grid.Column>
+                </Grid.Row>
+            </Grid>
+        </Segment>
+    );
+  }
+}
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