Fix digitalocean urls in docs

[skip ci]

website/source/docs/builders/digitalocean.html.markdown

@@ -55,7 +55,7 @@ each category, the available configuration keys are alphabetized.
 * `image` (string) - The name (or slug) of the base image to use. This is the
   image that will be used to launch a new droplet and provision it. This
   defaults to 'ubuntu-12-04-x64' which is the slug for "Ubuntu 12.04.4 x64".
-  See https://developers.digitalocean.com/#list-all-images for details on how to get a list of the the accepted image names/slugs.
+  See https://developers.digitalocean.com/documentation/v2/#list-all-images for details on how to get a list of the the accepted image names/slugs.
 
 * `image_id` (integer) - The ID of the base image to use. This is the image that
   will be used to launch a new droplet and provision it.
@@ -67,7 +67,7 @@ each category, the available configuration keys are alphabetized.
 * `region` (string) - The name (or slug) of the region to launch the droplet in.
   Consequently, this is the region where the snapshot will be available.
   This defaults to "nyc3", which is the slug for "New York 3".
-  See https://developers.digitalocean.com/v2/#regions for the accepted region names/slugs.
+  See https://developers.digitalocean.com/documentation/v2/#list-all-regions for the accepted region names/slugs.
 
 * `region_id` (integer) - The ID of the region to launch the droplet in. Consequently,
   this is the region where the snapshot will be available.
@@ -75,7 +75,7 @@ each category, the available configuration keys are alphabetized.
 
 * `size` (string) - The name (or slug) of the droplet size to use.
   This defaults to "512mb", which is the slug for "512MB".
-  See https://developers.digitalocean.com/#sizes for the accepted size names/slugs.
+  See https://developers.digitalocean.com/documentation/v2/#list-all-sizes for the accepted size names/slugs.
 
 * `size_id` (integer) - The ID of the droplet size to use.
   This setting is deprecated. Use `size` instead.