add "service" property to response

with this property, the user will know in which service the zipcode was
fetched

index.d.ts

@@ -4,7 +4,8 @@ declare module 'cep-promise' {
     state: string,
     city: string,
     street: string,
-    neighborhood: string
+    neighborhood: string,
+    service: string
   }
 
   // this workarround is because this : https://github.com/Microsoft/TypeScript/issues/5073
@@ -14,5 +15,3 @@ declare module 'cep-promise' {
 
   export = cep
 }
-
-

src/services/correios.js

@@ -71,7 +71,8 @@ function extractValuesFromSuccessResponse (xmlObject) {
     state: xmlObject.uf,
     city: xmlObject.cidade,
     neighborhood: xmlObject.bairro,
-    street: xmlObject.end
+    street: xmlObject.end,
+    service: 'correios',
   }
 }
 

src/services/viacep.js

@@ -42,7 +42,8 @@ function extractCepValuesFromResponse (responseObject) {
     state: responseObject.uf,
     city: responseObject.localidade,
     neighborhood: responseObject.bairro,
-    street: responseObject.logradouro
+    street: responseObject.logradouro,
+    service: 'viacep',
   }
 }
 

src/services/widenet.js

@@ -42,7 +42,8 @@ function extractCepValuesFromResponse (object) {
     state: object.state,
     city: object.city,
     neighborhood: object.district,
-    street: object.address
+    street: object.address,
+    service: 'widenet'
   }
 }