Credential APIs, client/server side component tests, APSARA.IO

- Added the missing credential APIs
- Added APSARA.IO component test
- Reorganized the component test framework to ease adding new
  server- and client-specific tests
- Added Krb5Config and Krb5Ktname to gssapi.Options, avoiding
  conflicts is up to the caller.
- Added multilevel log control in gssapi.Options

Author: lev

buffer_test.go

@@ -8,7 +8,7 @@ import (
 )
 
 func TestNewBuffer(t *testing.T) {
-	l, err := LoadLib(nil)
+	l, err := testLoad()
 	if err != nil {
 		t.Error(err)
 		return
@@ -38,7 +38,7 @@ func TestNewBuffer(t *testing.T) {
 
 // Also tests MakeBufferBytes, implicitly
 func TestMakeBufferString(t *testing.T) {
-	l, err := LoadLib(nil)
+	l, err := testLoad()
 	if err != nil {
 		t.Error(err)
 		return

component_test/client/main_test.go

@@ -242,7 +242,7 @@ func (lib *Lib) AcceptSecContext(
 
 	err = lib.MakeError(maj, min).GoError()
 	if err != nil {
-		lib.Print("AcceptSecContext: ", err)
+		lib.Err("AcceptSecContext: ", err)
 		return nil, nil, nil, nil, 0, 0, nil, err
 	}