add readme to doc-tests

Author: Jiloc

contrib/clarity-serialization/src/lib.rs

@@ -12,7 +12,7 @@
 //
 // You should have received a copy of the GNU General Public License
 // along with this program.  If not, see <http://www.gnu.org/licenses/>.
-
+#[doc = include_str!("../README.md")]
 #[macro_use]
 extern crate serde_derive;