Update package name (paritytech#52)

Author: en

Cargo.toml

@@ -31,7 +31,7 @@ pallet-indices = { git = "https://github.com/paritytech/substrate/", package = "
 substrate-rpc-api = { git = "https://github.com/paritytech/substrate/", package = "sc-rpc-api" }
 sp-rpc = { git = "https://github.com/paritytech/substrate/", package = "sp-rpc" }
 sp-core = { git = "https://github.com/paritytech/substrate/", package = "sp-core" }
-txpool-api = { git = "https://github.com/paritytech/substrate/", package = "sp-transaction-pool-api" }
+txpool-api = { git = "https://github.com/paritytech/substrate/", package = "sp-transaction-pool" }
 
 [dev-dependencies]
 env_logger = "0.7"