Enable #![deny(warnings)] on the main crate

Author: tomhoule

src/lib.rs

@@ -2,15 +2,15 @@
 //!
 //! The main interface to this library is the custom derive that generates modules from a GraphQL query and schema. See the docs for the [`GraphQLQuery`] trait for a full example.
 
+#![deny(warnings)]
 #![deny(missing_docs)]
 
 extern crate serde;
 #[macro_use]
 extern crate serde_derive;
-#[macro_use]
-extern crate graphql_query_derive;
+pub extern crate graphql_query_derive;
 
-#[macro_use]
+#[cfg_attr(test, macro_use)]
 extern crate serde_json;
 
 #[doc(hidden)]