Add showing version info in GUI

Resolves #373

src/views/About.vue

@@ -0,0 +1,51 @@
+<template>
+	<transition name="fade">
+		<div class="modal-mask hint-modal">
+			<div @click.self="$router.back()" class="modal-container">
+				<div class="modal-content">
+					<card
+						class="has-background-white has-no-shadow"
+						:title="$t('about.title')"
+						:has-close="true"
+						close-icon="times"
+						@close="$router.back()"
+						:padding="false"
+					>
+						<div class="p-4">
+							<p>
+								{{ $t('about.frontendVersion', {version: this.frontendVersion}) }}
+							</p>
+							<p>
+								{{ $t('about.apiVersion', {version: this.apiVersion}) }}
+							</p>
+						</div>
+						<footer class="modal-card-foot is-flex is-justify-content-flex-end">
+							<x-button
+								type="secondary"
+								@click.prevent.stop="$router.back()"
+							>
+								{{ $t('misc.close') }}
+							</x-button>
+						</footer>
+					</card>
+				</div>
+			</div>
+		</div>
+	</transition>
+</template>
+
+<script>
+import {VERSION} from '../version.json'
+
+export default {
+	name: 'About',
+	computed: {
+		frontendVersion() {
+			return VERSION
+		},
+		apiVersion() {
+			return this.$store.state.config.version
+		},
+	},
+}
+</script>