Added tls for http clients (#5766)

* Added global http client

* Added Do func for global http client

* Changed the code to use the global http client

* Fix http client in volume uploader

* Fixed pkg name

* Fixed http util funcs

* Fixed http client for bench_filer_upload

* Fixed http client for stress_filer_upload

* Fixed http client for filer_server_handlers_proxy

* Fixed http client for command_fs_merge_volumes

* Fixed http client for command_fs_merge_volumes and command_volume_fsck

* Fixed http client for s3api_server

* Added init global client for main funcs

* Rename global_client to client

* Changed:
- fixed NewHttpClient;
- added CheckIsHttpsClientEnabled func
- updated security.toml in scaffold

* Reduce the visibility of some functions in the util/http/client pkg

* Added the loadSecurityConfig function

* Use util.LoadSecurityConfiguration() in NewHttpClient func

weed/util/http/http_global_client_init.go

@@ -0,0 +1,27 @@
+package http
+
+import (
+	"github.com/seaweedfs/seaweedfs/weed/glog"
+	util_http_client "github.com/seaweedfs/seaweedfs/weed/util/http/client"
+)
+
+var (
+	globalHttpClient *util_http_client.HTTPClient
+)
+
+func NewGlobalHttpClient(opt ...util_http_client.HttpClientOpt) (*util_http_client.HTTPClient, error) {
+	return util_http_client.NewHttpClient(util_http_client.Client, opt...)
+}
+
+func GetGlobalHttpClient() *util_http_client.HTTPClient {
+	return globalHttpClient
+}
+
+func InitGlobalHttpClient() {
+	var err error
+
+	globalHttpClient, err = NewGlobalHttpClient()
+	if err != nil {
+		glog.Fatalf("error init global http client: %v", err)
+	}
+}