Add deprecation warnings for @0x/order-watcher

packages/order-watcher/README.md

@@ -1,4 +1,6 @@
-## OrderWatcher
+## OrderWatcher [Deprecated]
+
+:no_entry: WARNING: This project is deprecated. Please use [0x Mesh](https://github.com/0xProject/0x-mesh) for all your orderbook pruning needs. It can be used with or without order sharing enabled. If you have any questions about how to use Mesh, reach out to us in the [#mesh channel on Discord](https://discordapp.com/invite/d3FTX3M) :no_entry:
 
 An order watcher daemon that watches for order validity.
 

packages/website/md/docs/order_watcher/2/introduction.md

@@ -1 +1,3 @@
+**DEPRECATED: This project is deprecated. Please use [0x Mesh](https://github.com/0xProject/0x-mesh) for all your orderbook pruning needs. It can be used with or without order sharing enabled. If you have any questions about how to use Mesh, reach out to us in the [#mesh channel on Discord](https://discordapp.com/invite/d3FTX3M)**
+
 Welcome to the [order-watcher](https://github.com/0xProject/0x-monorepo/tree/development/packages/order-watcher) documentation! OrderWatcher is a daemon that efficiently watches a set of orders, emitting events whenever the validity of an order changes. It can be used by relayers to prune an orderbook, or by traders to keep orders fetched from a Relayer up-to-date.

packages/website/ts/pages/documentation/docs_home.tsx

@@ -134,7 +134,7 @@ const CATEGORY_TO_PACKAGES: ObjectMap<Package[]> = {
             description:
                 "A daemon that watches a set of 0x orders and emits events when an order's fillability has changed. Can be used by a relayer to prune their orderbook or by a trader to keep their view of the market up-to-date.",
             link: {
-                title: '@0x/order-watcher',
+                title: '@0x/order-watcher [Deprecated]',
                 to: WebsitePaths.OrderWatcher,
             },
         },