Feat: volume trajectory is a small multiples plot with no built-in filters (#43)

* Refactor in progress

* Add one small multiple volume trajectory

* Plot for every technology and add legend and footnote

* Wire up with selectors

* Change size depending on number of technologies

* Style

Author: MonikaFu

src/css/plot_styles.css

@@ -97,7 +97,7 @@ div.d3chart {
 	font-family: sans-serif;
 	font-size: 0.9em;
 	width: 100%;
-	max-width: 700px;
+	max-width: 1400px;
 	margin-top: 30px;
 	margin-bottom: 30px;
 }