dependency on package which will fail to compile in future version of Rust

[phansel]

xml-rpc-rs 0.0.12 depends on hyper 0.10.15, which depends on traitobject 0.1.0, which "contains code that will become an error in future versions of rust."

see: reem/rust-traitobject#8

[ssr-yuki]

From #2 (comment) , this issue can be resolved by merging either #2 or the development branch.

I am glad if @adnanademovic deals with this.