*: Include language/runtime version in output too

So it is less becomes less ambiguous when we update languages and check
them via helloweb.

Before:

    Hello world at `/`  ; Thu Jun  9 11:10:36 2016  (go)

After

    Hello world at `/`  ; Thu Jun  9 11:10:36 2016  (go devel +d66cbec Mon Jul 18 15:52:45 2016 +0000))

/reviewed-by TrustMe

go/helloweb.go

@@ -9,6 +9,7 @@ import (
 	"log"
 	"net"
 	"net/http"
+	"runtime"
 	"os"
 	"strings"
 	"time"
@@ -29,8 +30,8 @@ func logit(handler http.Handler) http.Handler {
 var name string
 
 func webhello(w http.ResponseWriter, r *http.Request) {
-	fmt.Fprintf(w, "Hello %s at `%s`  ; %s  (go)\n", name,
-		r.URL.Path, asctime())
+	fmt.Fprintf(w, "Hello %s at `%s`  ; %s  (go %s)\n", name,
+		r.URL.Path, asctime(), runtime.Version())
 }
 
 func main() {

python/helloweb.py

@@ -19,9 +19,9 @@ class WebHello(BaseHTTPRequestHandler):
         self.end_headers()
 
         print >>self.wfile, \
-            "Hello %s at `%s`  ; %s  (python)" % (
+            "Hello %s at `%s`  ; %s  (python %s)" % (
                 ' '.join(self.server.webhello_argv) or 'world',
-                self.path, time.asctime())
+                self.path, time.asctime(), sys.version.replace('\n', ' '))
 
 
 class HTTPServerV6(HTTPServer):

ruby/helloweb.rb

@@ -41,7 +41,7 @@ def main
     httpd.mount_proc '/' do |req, resp|
         name = args.argv_extra.join(' ')
         name = 'world' if name.empty?
-        resp.body = "Hello #{name} at `#{req.path}`  ; #{Time.now.asctime}  (ruby)\n"
+        resp.body = "Hello #{name} at `#{req.path}`  ; #{Time.now.asctime}  (#{RUBY_DESCRIPTION})\n"
     end
 
     httpd.start