fix(parser): parse Date type

Fixes #30

Author: merceyz

src/parser.ts

@@ -444,6 +444,7 @@ export function parseFromProgram(
 				case 'React.ReactNode': {
 					return t.unionNode([t.elementNode('node'), t.undefinedNode()]);
 				}
+				case 'Date':
 				case 'React.Component': {
 					return t.instanceOfNode(typeName);
 				}

test/date/input.d.ts

@@ -0,0 +1,6 @@
+type Props = {
+	createdAt: Date;
+	removedAt?: Date;
+};
+
+export default function Foo(props: Props): JSX.Element;

test/date/output.js

@@ -0,0 +1,4 @@
+Foo.propTypes = {
+	createdAt: PropTypes.instanceOf(Date).isRequired,
+	removedAt: PropTypes.instanceOf(Date),
+};

test/date/output.json

@@ -0,0 +1,26 @@
+{
+	"type": "ProgramNode",
+	"body": [
+		{
+			"type": "ComponentNode",
+			"name": "Foo",
+			"types": [
+				{
+					"type": "PropTypeNode",
+					"name": "createdAt",
+					"propType": { "type": "InstanceOfNode", "instance": "Date" },
+					"filenames": {}
+				},
+				{
+					"type": "PropTypeNode",
+					"name": "removedAt",
+					"propType": {
+						"type": "UnionNode",
+						"types": [{ "type": "UndefinedNode" }, { "type": "InstanceOfNode", "instance": "Date" }]
+					},
+					"filenames": {}
+				}
+			]
+		}
+	]
+}