fix(gtfs.yml): add more currency types for fares

fixes #550

gtfs.yml

@@ -629,9 +629,28 @@
     inputType: DROPDOWN
     bulkEditEnabled: true
     options:
-    - value: 'USD'
-    - value: 'EUR'
-    - value: 'GBP'
+    - value: USD
+      text: US dollar (USD)
+    - value: AUD
+      text: Australian dollar (AUD)
+    - value: CAD
+      text: Canadian dollar (CAD)
+    - value: CHF
+      text: Swiss franc (CHF)
+    - value: CNH
+      text: Chinese renminbi (CNH)
+    - value: EUR
+      text: Euro (EUR)
+    - value: GBP
+      text: Pound sterling (GBP)
+    - value: JPY
+      text: Japanese yen (JPY)
+    - value: MXN
+      text: Mexican peso (MXN)
+    - value: NZD
+      text: New Zealand dollar (NZD)
+    - value: SEK
+      text: Swedish krona (SEK)
     columnWidth: 12
     helpContent: "The currency_type field defines the currency used to pay the fare. Please use the ISO 4217 alphabetical currency codes which can be found at the following URL:http://en.wikipedia.org/wiki/ISO_4217."
   - name: "payment_method"