Update docs

docs/configuration.md

@@ -75,7 +75,7 @@ When WebP support detection is enabled, please take care to configure your CDN o
 
 ## Client Hints support
 
-imgproxy can use the `Width`, `Viewport-Width` or `DPR` HTTP header to determine the width of the image container using Client Hints when the width/dpr argument is ommited.
+imgproxy can use the `Width`, `Viewport-Width` or `DPR` HTTP headers to determine default width and DPR options using Client Hints. This feature is disabled by default and can be enabled by the following option:
 
 * `IMGPROXY_ENABLE_CLIENT_HINTS`: enables Client Hints support when the width is ommited for automatic responsive images . Read [here](https://developers.google.com/web/updates/2015/09/automating-resource-selection-with-client-hints) details about Client Hints.
 

docs/generating_the_url_advanced.md

@@ -86,6 +86,16 @@ Defines the height of the resulting image. When set to `0`, imgproxy will calcul
 
 Default: `0`
 
+##### Dpr
+
+```
+dpr:%dpr
+```
+
+When set, imgproxy will multiply the image dimensions according to this factor for HiDPI (Retina) devices. The value must be greater than 0.
+
+Default: `1`
+
 ##### Enlarge
 
 ```
@@ -158,16 +168,6 @@ When set, imgproxy will apply the gaussian blur filter to the resulting image. `
 
 Default: disabled
 
-##### Dpr
-
-```
-dpr:%dpr
-```
-
-When set, imgproxy will multiply the image dimensions according to this factor for HiDPI (Retina) devices. The value must be greater than 0.
-
-Default: `1`
-
 ##### Sharpen
 
 ```