adding a new endpoint on swagger

app/docs/boleto.yml

@@ -0,0 +1,48 @@
+Gera número para pagamento com boleto.
+---
+parameters:
+  - in: header
+    name: X-CLIENT
+    schema:
+      type: string
+    required: true
+  - in: body
+    name: data
+    required: true
+    schema:
+      id: Payload
+      required:
+        - amount
+      properties:
+        amount:
+           type: string
+        buyer:
+           type: object
+           properties:
+             name:
+               type: string
+             email:
+               type: string
+             cpf:
+               type: string
+responses:
+  200:
+    description: Retorna o número do boleto
+    schema:
+      type: object
+  403:
+    description: Cliente inválido.
+    schema:
+      type: object
+      properties:
+        errors:
+          type: object
+          properties:
+             client:
+               type: array
+               items:
+                 type: string
+  422:
+    description: Houve algum erro ao processar a requisição
+    schema:
+      type: object