Abstract getters on Luzon Zone are not static.

With the current definition, several items that are supposed to be public
members/methods are marked static. Since these are supposed to be returning
information for a particular zone, and in the luxon source they are not
static members/methods, they should not be marked as static. It is not
possible to create an implementation for Zone using the current definition.

References:
  https://moment.github.io/luxon/docs/class/src/zone.js~Zone.html
  https://github.com/moment/luxon/blob/master/src/zone.js

types/luxon/index.d.ts

@@ -5,6 +5,7 @@
 //                 Jonathan Siebern <https://github.com/jsiebern>
 //                 Matt R. Wilson <https://github.com/mastermatt>
 //                 Pietro Vismara <https://github.com/pietrovismara>
+//                 Janeene Beeforth <https://github.com/dawnmist>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
 // TypeScript Version: 2.2
 
@@ -467,11 +468,11 @@ export interface ZoneOffsetOptions {
 }
 
 export class Zone {
-    static offsetName(ts: number, options?: ZoneOffsetOptions): string;
-    static isValid: boolean;
-    static name: string;
-    static type: string;
-    static universal: boolean;
+    offsetName(ts: number, options?: ZoneOffsetOptions): string;
+    isValid: boolean;
+    name: string;
+    type: string;
+    universal: boolean;
     equals(other: Zone): boolean;
     offset(ts: number): number;
 }

types/luxon/luxon-tests.ts

@@ -1,4 +1,4 @@
-import { DateTime, Duration, Interval, Info, Settings, IANAZone } from 'luxon';
+import { DateTime, Duration, Interval, Info, Settings, IANAZone, Zone, ZoneOffsetOptions } from 'luxon';
 
 /* DateTime */
 const dt = DateTime.local(2017, 5, 15, 8, 30);
@@ -285,3 +285,21 @@ dur.reconfigure({ conversionAccuracy: 'longterm' }); // $ExpectType Duration
 
 start.until(end); // $ExpectType Interval
 i.toDuration(['years', 'months', 'days']); // $ExpectType Duration
+
+/* Sample Zone Implementation */
+class SampleZone extends Zone {
+  readonly isValid = false;
+  readonly name = 'Sample';
+  readonly type = 'Example';
+  readonly universal = true;
+
+  offsetName(ts: number, options?: ZoneOffsetOptions) {
+    return 'SampleZone';
+  }
+  equals(other: Zone) {
+    return other.name === this.name;
+  }
+  offset(ts: number) {
+    return 0;
+  }
+}