fix(readme): add links to documentation

ts/letterxpress.classes.account.ts

@@ -1,5 +1,16 @@
 import * as plugins from './letterxpress.plugins';
 
+export interface ILetterXpressConstructorOptions {
+  email: string;
+  apiKey: string;
+}
+
 export class LetterXpressAccount {
-  
-}
+  public options: ILetterXpressConstructorOptions;
+
+  constructor(optionsArg: ILetterXpressConstructorOptions) {
+    this.options = optionsArg;
+  }
+
+  public request() {}
+}

ts/letterxpress.plugins.ts

@@ -1,5 +1,3 @@
 import * as smartrequest from '@pushrocks/smartrequest';
 
-export {
-  smartrequest
-};
+export { smartrequest };