refactor code to use Shrinkwraprs and diesel-derive-newtype (#598)

* add shrinkwraprs and implement Id thru it

This also means we can automatically convert Id to String without using
.into()!

* cleanup with the help of clippy!

* cleanup with the help of cargo fmt!

* remove extra block

* Shrinkwrap Page, ContentLen and RemoteForm

* translations

plume-common/src/lib.rs

@@ -15,6 +15,8 @@ extern crate reqwest;
 extern crate rocket;
 extern crate serde;
 #[macro_use]
+extern crate shrinkwraprs;
+#[macro_use]
 extern crate serde_derive;
 #[macro_use]
 extern crate serde_json;