Migrate config to KV data format (#8392)

- adding oauth support to MinIO browser (#8400) by @kanagaraj
- supports multi-line get/set/del for all config fields
- add support for comments, allow toggle
- add extensive validation of config before saving
- support MinIO browser to support proper claims, using STS tokens
- env support for all config parameters, legacy envs are also
  supported with all documentation now pointing to latest ENVs
- preserve accessKey/secretKey from FS mode setups
- add history support implements three APIs
  - ClearHistory
  - RestoreHistory
  - ListHistory
- add help command support for each config parameters
- all the bug fixes after migration to KV, and other bug
  fixes encountered during testing.

cmd/config/cache/config_test.go

@@ -69,7 +69,7 @@ func TestParseCacheDrives(t *testing.T) {
 		}{"/home/drive{1..3}", []string{}, false})
 	}
 	for i, testCase := range testCases {
-		drives, err := parseCacheDrives(strings.Split(testCase.driveStr, cacheEnvDelimiter))
+		drives, err := parseCacheDrives(strings.Split(testCase.driveStr, cacheDelimiter))
 		if err != nil && testCase.success {
 			t.Errorf("Test %d: Expected success but failed instead %s", i+1, err)
 		}
@@ -98,7 +98,7 @@ func TestParseCacheExclude(t *testing.T) {
 	}
 
 	for i, testCase := range testCases {
-		excludes, err := parseCacheExcludes(strings.Split(testCase.excludeStr, cacheEnvDelimiter))
+		excludes, err := parseCacheExcludes(strings.Split(testCase.excludeStr, cacheDelimiter))
 		if err != nil && testCase.success {
 			t.Errorf("Test %d: Expected success but failed instead %s", i+1, err)
 		}