API to generate .rs files

API to generate .rs files to be used e. g. from build.rs.

Example code:

extern crate protoc_rust;

protoc_rust::run(protoc_rust::Args {
    out_dir: "src/protos",
    input: &["protos/a.proto", "b.proto"],
    includes: &["protos"],
}).expect("protoc");

Note this API requires protoc command present in $PATH. Although protoc-gen-rust command is not needed.