Documentation Revamp

Co-authored-by: jbdoumenjou <jb.doumenjou@gmail.com>

docs/content/middlewares/redirectregex.md

@@ -0,0 +1,52 @@
+# TODO - RedirectRegex
+
+Redirecting the Client to a Different Location
+{: .subtitle }
+
+`TODO: add schema`
+
+RegexRedirect redirect a request from an url to another with regex matching and replacement.
+
+## Configuration Examples
+
+??? example "File -- Redirect with domain replacement"
+
+    ```toml
+    [Middlewares]
+      [Middlewares.test-redirectregex.redirectregex]
+        regex = "^http://localhost/(.*)"
+        replacement = "http://mydomain/$1"
+    ```
+
+??? example "Docker -- Redirect with domain replacement"
+
+    ```yml
+     a-container:
+        image: a-container-image 
+            labels:
+                - "traefik.Middlewares.test-redirectregex.redirectregex.regex=^http://localhost/(.*)"
+                - "traefik.Middlewares.test-redirectregex.redirectregex.replacement=http://mydomain/$1"
+    ```
+
+## Configuration Options
+
+### permanent
+
+Set the `permanent` option to `true` to apply a permanent redirection.
+
+### regex
+
+The `Regex` option is the regular expression to match and capture elements form the request URL.
+
+!!! warning
+
+    Care should be taken when defining replacement expand variables: `$1x` is equivalent to `${1x}`, not `${1}x` (see [Regexp.Expand](https://golang.org/pkg/regexp/#Regexp.Expand)), so use `${1}` syntax.
+
+!!! tip
+
+    Regular expressions and replacements can be tested using online tools such as [Go Playground](https://play.golang.org/p/mWU9p-wk2ru) or the [Regex101](https://regex101.com/r/58sIgx/2).
+    
+### replacement
+
+The `replacement` option defines how to modify the URl to have the new target URL.
+