Move macaron to chi (#14293)

Use [chi](https://github.com/go-chi/chi) instead of the forked [macaron](https://gitea.com/macaron/macaron). Since macaron and chi have conflicts with session share, this big PR becomes a have-to thing. According my previous idea, we can replace macaron step by step but I'm wrong. :( Below is a list of big changes on this PR.

- [x] Define `context.ResponseWriter` interface with an implementation `context.Response`.
- [x] Use chi instead of macaron, and also a customize `Route` to wrap chi so that the router usage is similar as before.
- [x] Create different routers for `web`, `api`, `internal` and `install` so that the codes will be more clear and no magic .
- [x] Use https://github.com/unrolled/render instead of macaron's internal render
- [x] Use https://github.com/NYTimes/gziphandler instead of https://gitea.com/macaron/gzip
- [x] Use https://gitea.com/go-chi/session which is a modified version of https://gitea.com/macaron/session and removed `nodb` support since it will not be maintained. **BREAK**
- [x] Use https://gitea.com/go-chi/captcha which is a modified version of https://gitea.com/macaron/captcha
- [x] Use https://gitea.com/go-chi/cache which is a modified version of https://gitea.com/macaron/cache
- [x] Use https://gitea.com/go-chi/binding which is a modified version of https://gitea.com/macaron/binding
- [x] Use https://github.com/go-chi/cors instead of https://gitea.com/macaron/cors
- [x] Dropped https://gitea.com/macaron/i18n and make a new one in `code.gitea.io/gitea/modules/translation`
- [x] Move validation form structs from `code.gitea.io/gitea/modules/auth` to `code.gitea.io/gitea/modules/forms` to avoid dependency cycle.
- [x] Removed macaron log service because it's not need any more. **BREAK**
- [x] All form structs have to be get by `web.GetForm(ctx)` in the route function but not as a function parameter on routes definition.
- [x] Move Git HTTP protocol implementation to use routers directly.
- [x] Fix the problem that chi routes don't support trailing slash but macaron did.
- [x] `/api/v1/swagger` now will be redirect to `/api/swagger` but not render directly so that `APIContext` will not create a html render. 

Notices:
- Chi router don't support request with trailing slash
- Integration test `TestUserHeatmap` maybe mysql version related. It's failed on my macOS(mysql 5.7.29 installed via brew) but succeed on CI.

Co-authored-by: 6543 <6543@obermui.de>

routers/private/mail.go

@@ -11,17 +11,17 @@ import (
 	"strconv"
 
 	"code.gitea.io/gitea/models"
+	"code.gitea.io/gitea/modules/context"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/private"
 	"code.gitea.io/gitea/modules/setting"
 	"code.gitea.io/gitea/services/mailer"
-	"gitea.com/macaron/macaron"
 )
 
 // SendEmail pushes messages to mail queue
 //
 // It doesn't wait before each message will be processed
-func SendEmail(ctx *macaron.Context) {
+func SendEmail(ctx *context.PrivateContext) {
 	if setting.MailService == nil {
 		ctx.JSON(http.StatusInternalServerError, map[string]interface{}{
 			"err": "Mail service is not enabled.",
@@ -30,7 +30,7 @@ func SendEmail(ctx *macaron.Context) {
 	}
 
 	var mail private.Email
-	rd := ctx.Req.Body().ReadCloser()
+	rd := ctx.Req.Body
 	defer rd.Close()
 	if err := json.NewDecoder(rd).Decode(&mail); err != nil {
 		log.Error("%v", err)
@@ -77,7 +77,7 @@ func SendEmail(ctx *macaron.Context) {
 	sendEmail(ctx, mail.Subject, mail.Message, emails)
 }
 
-func sendEmail(ctx *macaron.Context, subject, message string, to []string) {
+func sendEmail(ctx *context.PrivateContext, subject, message string, to []string) {
 	for _, email := range to {
 		msg := mailer.NewMessage([]string{email}, subject, message)
 		mailer.SendAsync(msg)