readme: add tools download page (#855)

* readme: add tools download page

* download: address comments

* *: address comments and update content

* tools: add two links

README.md

@@ -159,6 +159,7 @@
   - [PD Recover](tools/pd-recover.md)
   - [TiKV Control](https://github.com/tikv/tikv/blob/master/docs/tools/tikv-control.md)
   - [TiDB Controller](tools/tidb-controller.md)
+  - [Download](tools/download.md)
 + [TiKV Documentation](https://github.com/tikv/tikv/wiki)
 + TiSpark Documentation
   - [Quick Start Guide](tispark/tispark-quick-start-guide.md)

tools/download.md

@@ -0,0 +1,45 @@
+---
+title: Download
+summary: Download the most officially maintained versions of TiDB enterprise tools.
+category: resources
+---
+
+# Download
+
+This document collects the available downloads for most officially maintained versions of TiDB enterprise tools.
+
+## TiDB-Binlog and Lightning
+
+If you want to download the latest version of [TiDB-Binlog](../tools/tidb-binlog-cluster.md) or [Lightning](https://github.com/pingcap/tidb-lightning), directly download the TiDB package, because both TiDB-Binlog and Lightning are included in the TiDB package.
+
+In addition, the Kafka version of TiDB-Binlog is also provided.
+
+| Package name | OS | Architecture | SHA256 checksum |
+|:---|:---|:---|:---|
+| [tidb-latest-linux-amd64.tar.gz](http://download.pingcap.org/tidb-latest-linux-amd64.tar.gz) (TiDB-Binlog, Lightning) | Linux | amd64 |[tidb-latest-linux-amd64.sha256](http://download.pingcap.org/tidb-latest-linux-amd64.sha256)|
+| [tidb-binlog-kafka-linux-amd64.tar.gz](http://download.pingcap.org/tidb-binlog-kafka-linux-amd64.tar.gz) (the Kafka version of TiDB-Binlog) | Linux | amd64 |[tidb-binlog-kafka-linux-amd64.sha256](http://download.pingcap.org/tidb-binlog-kafka-linux-amd64.sha256)|
+
+## TiDB-DM (Data Migration)
+
+If you want to download the latest version of TiDB-DM, click the download link in the following table. You can also check the [DM Release](https://github.com/pingcap/dm/releases) page.
+
+| Package name | OS | Architecture |  SHA256 checksum |
+|:---|:---|:---|:---|
+| [dm-latest-linux-amd64.tar.gz](http://download.pingcap.org/dm-latest-linux-amd64.tar.gz) | Linux | amd64 | [dm-latest-linux-amd64.sha256](http://download.pingcap.org/dm-latest-linux-amd64.sha256) |
+
+## Syncer, Loader, and mydumper
+
+If you want to download the latest version of [Syncer](../tools/syncer.md), [Loader](../tools/loader.md), or [mydumper](../tools/mydumper.md), directly download the tidb-enterprise-tools package, because all these tools are included in this package.
+
+| Package name | OS | Architecture | SHA256 checksum |
+|:---|:---|:---|:---|
+| [tidb-enterprise-tools-latest-linux-amd64.tar.gz](http://download.pingcap.org/tidb-enterprise-tools-latest-linux-amd64.tar.gz) | Linux | amd64 | [tidb-enterprise-tools-latest-linux-amd64.sha256](http://download.pingcap.org/tidb-enterprise-tools-latest-linux-amd64.sha256) |
+
+This enterprise tools package includes all the following tools:
+
+- Syncer
+- Loader
+- mydumper
+- [binlogctl](../tools/tidb-binlog-cluster.md#binlogctl-guide)
+- ddl_checker
+- [sync_diff_inspector](../tools/sync-diff-inspector.md)