First version of side panel with person details.

Currently hidden. Can be shown by adding &sidePanel=true to URL.
Will be shown by default when it's ready.

src/parse-gedcom.d.ts

@@ -0,0 +1,12 @@
+// Data type definitions for the parse-gedcom library.
+declare module 'parse-gedcom' {
+  interface GedcomEntry {
+    level: number;
+    pointer: string;
+    tag: string;
+    data: string;
+    tree: GedcomEntry[];
+  }
+
+  export function parse(input: string): GedcomEntry[];
+}