vendor: add j-keck/arping

vendor/github.com/j-keck/arping/README.md

@@ -0,0 +1,29 @@
+# arping
+  
+arping is a native go library to ping a host per arp datagram, or query a host mac address 
+
+The currently supported platforms are: Linux and BSD.
+   
+
+## Usage
+### arping library
+
+* import this library per `import "github.com/j-keck/arping"`
+* export GOPATH if not already (`export GOPATH=$PWD`)
+* download the library `go get`
+* run it `sudo -E go run <YOUR PROGRAMM>` 
+* or build it `go build`
+
+
+The library requires raw socket access. So it must run as root, or with appropriate capabilities under linux: `sudo setcap cap_net_raw+ep <BIN>`.
+
+For api doc and examples see: [godoc](http://godoc.org/github.com/j-keck/arping) or check the standalone under 'cmd/arping/main.go'.
+
+
+    
+### arping executable
+   
+To get a runnable pinger use `go get -u github.com/j-keck/arping/cmd/arping`. This will build the binary in $GOPATH/bin.
+
+arping requires raw socket access. So it must run as root, or with appropriate capabilities under Linux: `sudo setcap cap_net_raw+ep <ARPING_PATH>`.
+