Fixed typo

Author: sebright

json-rpc-server.cabal

@@ -12,7 +12,7 @@ build-type:          Simple
 extra-source-files:  README.md
 cabal-version:       >=1.8
 tested-with:         GHC == 7.4.1, GHC == 7.6.3
-description:         An implemation of the server side of JSON RPC 2.0.
+description:         An implementation of the server side of JSON RPC 2.0.
                      See <http://www.jsonrpc.org/specification>. This
                      library uses 'ByteString' for input and output,
                      leaving the choice of transport up to the user.