rpc/client: add Events method to the client interface (#7982)

- Update documentation to deprecate the old methods.
- Add Events methods to HTTP, WS, and Local clients.
- Add Events method to the light client wrapper.
- Rename legacy events client to SubscriptionClient.

rpc/test/helpers.go

@@ -67,6 +67,7 @@ func CreateConfig(t *testing.T, testName string) (*config.Config, error) {
 	p2pAddr, rpcAddr := makeAddrs()
 	c.P2P.ListenAddress = p2pAddr
 	c.RPC.ListenAddress = rpcAddr
+	c.RPC.EventLogWindowSize = 5 * time.Minute
 	c.Consensus.WalPath = "rpc-test"
 	c.RPC.CORSAllowedOrigins = []string{"https://tendermint.com/"}
 	return c, nil