JSON: remove redundant word "channel" from direction fields.

Suggested-by: @cdecker
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

CHANGELOG.md

@@ -11,8 +11,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 - plugins: fully enabled, and ready for you to write some!
 - lightning-cli: `help <cmd>` finds man pages even if `make install` not run.
-- JSON API: `waitsendpay` now has an `erring_channel_direction` field.
-- JSON API: `listpeers` now has a `channel_direction` field in `channels`.
+- JSON API: `waitsendpay` now has an `erring_direction` field.
+- JSON API: `listpeers` now has a `direction` field in `channels`.
 - JSON API: `listchannels` now takes a `source` option to filter by node id.
 
 ### Changed

lightningd/pay.c

@@ -944,7 +944,7 @@ static void json_waitsendpay_on_resolve(const struct sendpay_result *r,
 			json_add_pubkey(data, "erring_node", &fail->erring_node);
 			json_add_short_channel_id(data, "erring_channel",
 						  &fail->erring_channel);
-			json_add_num(data, "erring_channel_direction",
+			json_add_num(data, "erring_direction",
 				     fail->channel_dir);
 			if (fail->channel_update)
 				json_add_hex_talarr(data, "channel_update",

lightningd/peer_control.c

@@ -707,7 +707,7 @@ static void json_add_peer(struct lightningd *ld,
 			json_add_short_channel_id(response,
 						  "short_channel_id",
 						  channel->scid);
-			json_add_num(response, "channel_direction",
+			json_add_num(response, "direction",
 				     pubkey_idx(&ld->id, &p->id));
 		}
 		derive_channel_id(&cid,