Error in UploadFiles, UploadType in multiple mutation

[Makoto2805]

Use two mutation CreateUser and CreateBook, use UploadType in two mutation
generate error Schema must contain unique named types but contains multiple types named \"Upload\" (see http://webonyx.github.io/graphql-php/type-system/#type-registry).

but use UploadType only mutation no view error

[rebing]

#126 Added a name attribute to UploadType constructor