Add getWalletFiles method

Breeze.UI/db.json

 {
-    "create":
-    {
-        "mnemonic": "foo bar buz"
-    },
-    "load":
-    {
-        "success": "true"
+    "files": {
+        "walletsPath": "/home/dev0tion/Desktop/Wallets",
+        "walletsFiles": [
+            "myFirstWallet.json",
+            "mySecondWallet.json"
+        ]
     },
     "status":
     {

Breeze.UI/src/app/shared/api/api.service.ts

@@ -21,6 +21,15 @@ export class ApiService {
     private webApiUrl = 'http://localhost:5000/api/v1';
     private headers = new Headers({'Content-Type': 'application/json'});
 
+    /**
+     * Gets available wallets at the default path
+     */
+     getWalletFiles(): Observable<any> {
+        return this.http
+          .get(this.mockApiUrl + '/wallet/files')
+          .map((response: Response) => response);
+     }
+
     /**
      * Create a new wallet.
      */