docs: add Scaleway documentation

Signed-off-by: Alexandre NICOLAIE <alexandre.nicolaie@gmail.com>

website/source/docs/builders/scaleway.html.md

@@ -74,11 +74,14 @@ builder.
     appear in your account. Default `packer-TIMESTAMP`
 
 -   `boottype` (string) - The type of boot, can be either `local` or
-    `bootscript`, Default `bootscript`
+    `bootscript`. Default `bootscript`
 
 -   `bootscript` (string) - The id of an existing bootscript to use when
     booting the server.
 
+-   `remove_volume` (boolean) - Force Packer to delete volume associated with 
+    the resulting snapshot after the build. Default `false`.
+
 ## Basic Example
 
 Here is a basic example. It is completely valid as soon as you enter your own