Catch all exceptions on Deserialize

If you look at the source of NewtonSoft.Json, you'll see that DeserializeObject never throws an IOException. All exceptions should be caught in this method, just like Serialize.

modules/swagger-codegen/src/main/resources/csharp/ApiClient.mustache

@@ -235,7 +235,7 @@ namespace {{packageName}}.Client
             {
                 return JsonConvert.DeserializeObject(content, type);
             }
-            catch (IOException e)
+            catch (Exception e)
             {
                 throw new ApiException(500, e.Message);
             }