Added Table of Contents to long documentation pages (#13890)

* Redo #13836 with new shortcode
(https://gitea.com/gitea/theme/pulls/90)

* add Api Usage

Co-authored-by: techknowlogick <techknowlogick@gitea.io>

docs/content/doc/usage/reverse-proxies.en-us.md

@@ -13,7 +13,11 @@ menu:
     identifier: "reverse-proxies"
 ---
 
-##  Using Nginx as a reverse proxy
+# Reverse Proxies
+
+{{< toc >}}
+
+##  Nginx
 If you want Nginx to serve your Gitea instance, add the following `server` section to the `http` section of `nginx.conf`:
 
 ```
@@ -27,7 +31,7 @@ server {
 }
 ```
 
-## Using Nginx with a sub-path as a reverse proxy
+## Nginx with a sub-path
 
 In case you already have a site, and you want Gitea to share the domain name, you can setup Nginx to serve Gitea under a sub-path by adding the following `server` section inside the `http` section of `nginx.conf`:
 
@@ -44,7 +48,7 @@ server {
 
 Then set `[server] ROOT_URL = http://git.example.com/git/` in your configuration.
 
-##  Using Nginx as a reverse proxy and serve static resources directly
+##  Nginx and serve static resources directly
 We can tune the performance in splitting requests into categories static and dynamic.
 
 CSS files, JavaScript files, images and web fonts are static content.
@@ -61,7 +65,7 @@ After this, run `make frontend` in the repository directory to generate the stat
 Depending on the scale of your user base, you might want to split the traffic to two distinct servers,
  or use a cdn for the static files.
 
-### using a single node and a single domain
+### Single node and single domain
 
 Set `[server] STATIC_URL_PREFIX = /_/static` in your configuration.
 
@@ -80,7 +84,7 @@ server {
 }
 ```
 
-### using two nodes and two domains
+### Two nodes and two domains
 
 Set `[server] STATIC_URL_PREFIX = http://cdn.example.com/gitea` in your configuration.
 
@@ -112,7 +116,7 @@ server {
 }
 ```
 
-## Using Apache HTTPD as a reverse proxy
+## Apache HTTPD
 
 If you want Apache HTTPD to serve your Gitea instance, you can add the following to your Apache HTTPD configuration (usually located at `/etc/apache2/httpd.conf` in Ubuntu):
 
@@ -131,7 +135,7 @@ Note: The following Apache HTTPD mods must be enabled: `proxy`, `proxy_http`
 
 If you wish to use Let's Encrypt with webroot validation, add the line `ProxyPass /.well-known !` before `ProxyPass` to disable proxying these requests to Gitea.
 
-## Using Apache HTTPD with a sub-path as a reverse proxy
+## Apache HTTPD with a sub-path
 
 In case you already have a site, and you want Gitea to share the domain name, you can setup Apache HTTPD to serve Gitea under a sub-path by adding the following to you Apache HTTPD configuration (usually located at `/etc/apache2/httpd.conf` in Ubuntu):
 
@@ -153,7 +157,7 @@ Then set `[server] ROOT_URL = http://git.example.com/git/` in your configuration
 
 Note: The following Apache HTTPD mods must be enabled: `proxy`, `proxy_http`
 
-## Using Caddy as a reverse proxy
+## Caddy
 
 If you want Caddy to serve your Gitea instance, you can add the following server block to your Caddyfile:
 
@@ -171,7 +175,7 @@ git.example.com {
 }
 ```
 
-## Using Caddy with a sub-path as a reverse proxy
+## Caddy with a sub-path
 
 In case you already have a site, and you want Gitea to share the domain name, you can setup Caddy to serve Gitea under a sub-path by adding the following to your server block in your Caddyfile:
 
@@ -194,7 +198,7 @@ git.example.com {
 
 Then set `[server] ROOT_URL = http://git.example.com/git/` in your configuration.
 
-## Using IIS as a reverse proxy
+## IIS
 
 If you wish to run Gitea with IIS. You will need to setup IIS with URL Rewrite as reverse proxy.