Doc: add installtion instructions for tools

Add missing install commands. Update benchmark to go install as go
get usage is deprecated. Also, improve overall instructions and
experience.

related etcd-io#13991

Author: spzala

tools/benchmark/README.md

@@ -2,13 +2,30 @@
 
 `etcd/tools/benchmark` is the official benchmarking tool for etcd clusters.
 
-## Install
+## Installation
 
-To install `benchmark` follow these steps.
+Install the tool by running the following command from the etcd source directory.
 
-```sh
-$ go get go.etcd.io/etcd/v3/tools/benchmark
-$ benchmark --help
 ```
+  $ go install -v ./tools/benchmark
+```
+
+The installation will place executables in the $GOPATH/bin. If $GOPATH environment variable is not set, the tool will be installed into the $HOME/go/bin. You can also find out the installed location by running the following command from the etcd source directory. Make sure that $PATH is set accordingly in your environment.
 
-Last command should output of usage of `benchmark`.
+```
+  $ go list -f "{{.Target}}" ./tools/benchmark
+```
+
+Alternatively, instead of installing the tool, you can use it by simply running the following command from the etcd source directory.
+
+```
+  $ go run ./tools/benchmark
+```
+
+## Usage
+
+The following command should output the usage per the latest development.
+
+```
+  $ benchmark --help
+```

tools/etcd-dump-db/README.md

@@ -1,6 +1,36 @@
-### etcd-dump-db
+# etcd-dump-db
 
-etcd-dump-db inspects etcd db files.
+`etcd-dump-db` inspects etcd db files.
+
+## Installation
+
+Install the tool by running the following command from the etcd source directory.
+
+```
+  $ go install -v ./tools/etcd-dump-db
+```
+
+The installation will place executables in the $GOPATH/bin. If $GOPATH environment variable is not set, the tool will be installed into the $HOME/go/bin. You can also find out the installed location by running the following command from the etcd source directory. Make sure that $PATH is set accordingly in your environment.
+
+```
+  $ go list -f "{{.Target}}" ./tools/etcd-dump-db
+```
+
+Alternatively, instead of installing the tool, you can use it by simply running the following command from the etcd source directory.
+
+```
+  $ go run ./tools/etcd-dump-db
+```
+
+## Usage
+
+The following command should output the usage per the latest development.
+
+```
+  $ etcd-dump-db --help
+```
+
+An example of usage detail is provided below.
 
 ```
 Usage:

tools/etcd-dump-logs/README.md

@@ -1,6 +1,36 @@
-### etcd-dump-logs
+# etcd-dump-logs
 
-etcd-dump-logs dumps the log from data directory.
+`etcd-dump-logs` dumps the log from data directory.
+
+## Installation
+
+Install the tool by running the following command from the etcd source directory.
+
+```
+  $ go install -v ./tools/etcd-dump-logs
+```
+
+The installation will place executables in the $GOPATH/bin. If $GOPATH environment variable is not set, the tool will be installed into the $HOME/go/bin. You can also find out the installed location by running the following command from the etcd source directory. Make sure that $PATH is set accordingly in your environment.
+
+```
+  $ go list -f "{{.Target}}" ./tools/etcd-dump-logs
+```
+
+Alternatively, instead of installing the tool, you can use it by simply running the following command from the etcd source directory.
+
+```
+  $ go run ./tools/etcd-dump-logs
+```
+
+## Usage
+
+The following command should output the usage per the latest development.
+
+```
+  $ etcd-dump-logs --help
+```
+
+An example of usage detail is provided below.
 
 ```
 Usage:

tools/etcd-dump-metrics/README

@@ -0,0 +1,53 @@
+# etcd-dump-metrics
+
+ `etcd-dump-metrics` provides metrics for the latest main branch, a given endpoint, or version.
+
+## Installation
+
+Install the tool by running the following command from the etcd source directory.
+
+```
+  $ go install -v ./tools/etcd-dump-metrics
+```
+
+The installation will place executables in the $GOPATH/bin. If $GOPATH environment variable is not set, the tool will be
+installed into the $HOME/go/bin. You can also find out the installed location by running the following command from the
+etcd source directory. Make sure that $PATH is set accordingly in your environment.
+
+```
+  $ go list -f "{{.Target}}" ./tools/etcd-dump-metrics
+```
+
+Alternatively, instead of installing the tool, you can use it by simply running the following command from the etcd source
+directory.
+
+```
+  $ go run ./tools/etcd-dump-metrics
+```
+
+## Usage
+
+The following command should output the usage per the latest development.
+
+```
+  $ etcd-dump-metrics --help
+```
+
+An example of usage detail is provided below.
+
+### For the latest main branch
+```
+  $ etcd-dump-metrics
+```
+
+### For the provided endpoint
+```
+  $ goreman start
+  $ etcd-dump-metrics --addr http://localhost:2379/metrics
+```
+
+### Download specific version to temporary directory to fetch metrics
+```
+  $ etcd-dump-metrics --debug --download-ver v3.5.3
+  $ etcd-dump-metrics --download-ver v3.5.3
+```