Changelog, credit and doc refresh for #1121

docs/api-output.md

@@ -183,6 +183,7 @@ Use a `.zip` or `.szi` file extension with `toFile` to write to a compressed arc
 -   `tile` **[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)?** 
     -   `tile.size` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** tile size in pixels, a value between 1 and 8192. (optional, default `256`)
     -   `tile.overlap` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** tile overlap in pixels, a value between 0 and 8192. (optional, default `0`)
+    -   `tile.angle` **[Number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** tile angle of rotation, must be a multiple of 90. (optional, default `0`)
     -   `tile.container` **[String](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String)** tile container, with value `fs` (filesystem) or `zip` (compressed file). (optional, default `'fs'`)
     -   `tile.layout` **[String](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String)** filesystem layout, possible values are `dz`, `zoomify` or `google`. (optional, default `'dz'`)
 

docs/changelog.md

@@ -10,6 +10,10 @@ Requires libvips v8.6.1.
   [#1024](https://github.com/lovell/sharp/pull/1024)
   [@3epnm](https://github.com/3epnm)
 
+* Expose angle option for tile-based output.
+  [#1121](https://github.com/lovell/sharp/pull/1121)
+  [@BiancoA](https://github.com/BiancoA)
+
 #### v0.19.0 - 11<sup>th</sup> January 2018
 
 * Expose offset coordinates of strategy-based crop.

docs/index.md

@@ -107,6 +107,7 @@ the help and code contributions of the following people:
 * [Kenric D'Souza](https://github.com/AzureByte)
 * [Oleh Aleinyk](https://github.com/oaleynik)
 * [Marcel Bretschneider](https://github.com/3epnm)
+* [Andrea Bianco](https://github.com/BiancoA)
 
 Thank you!