Revert "Add yet-another-react-lightbox package and update .gitignore to exclude node_modules"

This reverts commit c92f4a5edd.

frontend/node_modules/react-dropzone/examples/class-component/README.md

@@ -0,0 +1,45 @@
+If you're still using class components, you can use the [`<Dropzone>`](https://react-dropzone.js.org/#components) component provided by the lib:
+
+```jsx harmony
+import React, {Component} from 'react';
+import Dropzone from 'react-dropzone';
+
+class Basic extends Component {
+  constructor() {
+    super();
+    this.onDrop = (files) => {
+      this.setState({files})
+    };
+    this.state = {
+      files: []
+    };
+  }
+
+  render() {
+    const files = this.state.files.map(file => (
+      <li key={file.name}>
+        {file.name} - {file.size} bytes
+      </li>
+    ));
+
+    return (
+      <Dropzone onDrop={this.onDrop}>
+        {({getRootProps, getInputProps}) => (
+          <section className="container">
+            <div {...getRootProps({className: 'dropzone'})}>
+              <input {...getInputProps()} />
+              <p>Drag 'n' drop some files here, or click to select files</p>
+            </div>
+            <aside>
+              <h4>Files</h4>
+              <ul>{files}</ul>
+            </aside>
+          </section>
+        )}
+      </Dropzone>
+    );
+  }
+}
+
+<Basic />
+```