Compute Acceptance Test Changes (#33)

This commit makes more changes to the compute acceptance tests:

* Makes all reusable functions exportable so other APIs can use them.
* Centralizes client initialization and environment variable checks.
diff --git a/acceptance/openstack/compute/v2/quotaset_test.go b/acceptance/openstack/compute/v2/quotaset_test.go
index 60b8563..d9e73e9 100644
--- a/acceptance/openstack/compute/v2/quotaset_test.go
+++ b/acceptance/openstack/compute/v2/quotaset_test.go
@@ -7,17 +7,18 @@
 	"testing"
 
 	"github.com/gophercloud/gophercloud"
+	"github.com/gophercloud/gophercloud/acceptance/clients"
 	"github.com/gophercloud/gophercloud/openstack/compute/v2/extensions/quotasets"
 	"github.com/gophercloud/gophercloud/openstack/identity/v2/tenants"
 )
 
 func TestQuotasetGet(t *testing.T) {
-	client, err := newClient()
+	client, err := clients.NewComputeV2Client()
 	if err != nil {
 		t.Fatalf("Unable to create a compute client: %v", err)
 	}
 
-	identityClient, err := newIdentityClient()
+	identityClient, err := clients.NewIdentityV2Client()
 	if err != nil {
 		t.Fatalf("Unable to get a new identity client: %v", err)
 	}
@@ -32,7 +33,7 @@
 		t.Fatal(err)
 	}
 
-	printQuotaSet(t, quotaSet)
+	PrintQuotaSet(t, quotaSet)
 }
 
 func getTenantID(t *testing.T, client *gophercloud.ServiceClient) (string, error) {
@@ -52,18 +53,3 @@
 
 	return "", fmt.Errorf("Unable to get tenant ID")
 }
-
-func printQuotaSet(t *testing.T, quotaSet *quotasets.QuotaSet) {
-	t.Logf("instances: %d\n", quotaSet.Instances)
-	t.Logf("cores: %d\n", quotaSet.Cores)
-	t.Logf("ram: %d\n", quotaSet.Ram)
-	t.Logf("key_pairs: %d\n", quotaSet.KeyPairs)
-	t.Logf("metadata_items: %d\n", quotaSet.MetadataItems)
-	t.Logf("security_groups: %d\n", quotaSet.SecurityGroups)
-	t.Logf("security_group_rules: %d\n", quotaSet.SecurityGroupRules)
-	t.Logf("fixed_ips: %d\n", quotaSet.FixedIps)
-	t.Logf("floating_ips: %d\n", quotaSet.FloatingIps)
-	t.Logf("injected_file_content_bytes: %d\n", quotaSet.InjectedFileContentBytes)
-	t.Logf("injected_file_path_bytes: %d\n", quotaSet.InjectedFilePathBytes)
-	t.Logf("injected_files: %d\n", quotaSet.InjectedFiles)
-}