Go: changing import name for "unit.nginx.org/go".

This patch includes packaging changes - update unit-go installation
directory.

test/go/404/app.go

@@ -4,7 +4,7 @@ import (
 	"io"
 	"io/ioutil"
 	"net/http"
-	"nginx/unit"
+	"unit.nginx.org/go"
 )
 
 func handler(w http.ResponseWriter, r *http.Request) {

test/go/command_line_arguments/app.go

@@ -4,7 +4,7 @@ import (
 	"fmt"
 	"io"
 	"net/http"
-	"nginx/unit"
+	"unit.nginx.org/go"
 	"os"
 	"strings"
 )

test/go/cookies/app.go

@@ -2,7 +2,7 @@ package main
 
 import (
 	"net/http"
-	"nginx/unit"
+	"unit.nginx.org/go"
 )
 
 func handler(w http.ResponseWriter, r *http.Request) {

test/go/empty/app.go

@@ -2,7 +2,7 @@ package main
 
 import (
 	"net/http"
-	"nginx/unit"
+	"unit.nginx.org/go"
 )
 
 func handler(w http.ResponseWriter, r *http.Request) {}

test/go/get_variables/app.go

@@ -2,7 +2,7 @@ package main
 
 import (
 	"net/http"
-	"nginx/unit"
+	"unit.nginx.org/go"
 )
 
 func handler(w http.ResponseWriter, r *http.Request) {

test/go/mirror/app.go

@@ -4,7 +4,7 @@ import (
 	"fmt"
 	"io"
 	"net/http"
-	"nginx/unit"
+	"unit.nginx.org/go"
 )
 
 func handler(w http.ResponseWriter, r *http.Request) {

test/go/ns_inspect/app.go

@@ -4,7 +4,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"net/http"
-	"nginx/unit"
+	"unit.nginx.org/go"
 	"os"
 	"strconv"
 )

test/go/post_variables/app.go

@@ -2,7 +2,7 @@ package main
 
 import (
 	"net/http"
-	"nginx/unit"
+	"unit.nginx.org/go"
 )
 
 func handler(w http.ResponseWriter, r *http.Request) {

test/go/variables/app.go

@@ -4,7 +4,7 @@ import (
 	"fmt"
 	"io"
 	"net/http"
-	"nginx/unit"
+	"unit.nginx.org/go"
 )
 
 func handler(w http.ResponseWriter, r *http.Request) {