Dashboard loading (#142)

* Fixed: Loading indicator never appears
Added: Loading indicator to dashboard when loading first results

* Less assumptions

* Fixes: Image uploads not working

* Fixes #136 - Keyboard shortcuts should work when editor is not focused

* Allow images to be dragged anywhere on document editor

* Fixes #137 - vertical alignment

* Restore shortcuts with editor focus

* Restore 'e' to edit current document
Fixed up ? to open keyboard shortcuts

* wip

* LoadinglistPlaceholder

* WIP

* Refactor

* DRY logic

frontend/components/LoadingPlaceholder/components/Mask.js

@@ -0,0 +1,38 @@
+// @flow
+import React, { Component } from 'react';
+import styled from 'styled-components';
+import { pulsate } from 'styles/animations';
+import { color } from 'styles/constants';
+import { randomInteger } from 'utils/random';
+import Flex from 'components/Flex';
+
+class Mask extends Component {
+  width: number;
+
+  shouldComponentUpdate() {
+    return false;
+  }
+
+  constructor(props: Object) {
+    super(props);
+    this.width = randomInteger(75, 100);
+  }
+
+  render() {
+    return <Redacted width={this.width} {...this.props} />;
+  }
+}
+
+const Redacted = styled(Flex)`
+  width: ${props => (props.header ? props.width / 2 : props.width)}%;
+  height: ${props => (props.header ? 28 : 18)}px;
+  margin-bottom: ${props => (props.header ? 18 : 12)}px;
+  background-color: ${color.smokeDark};
+  animation: ${pulsate} 1.3s infinite;
+
+  &:last-child {
+    margin-bottom: 0;
+  }
+`;
+
+export default Mask;