Update documentation

README.md

@@ -122,9 +122,15 @@ to the 'Sitemap generation interval' setting.
 A manual generation is possible on admin/config/search/simplesitemap. This is
 also the place that shows the overall and variant specific generation status.
 
-The sitemap can be also generated via drush: Use the command
-'drush simple-sitemap:generate' ('ssg'), or 'drush simple-sitemap:rebuild-queue'
-('ssr').
+The sitemap can be also generated via drush:
+ * `simple-sitemap:generate` or `ssg`: Generates the sitemap (continues
+   generating from queue, or rebuilds queue for all variants beforehand if
+   nothing is queued).
+   
+ * `simple-sitemap:rebuild-queue` or `ssr`: Deletes queue and queues elements
+   for all or specific sitemap variants. Add `--variants` flag and specify a
+   comma separated list of variants if wanting to queue only specific variants
+   for the upcoming generation.
 
 Generation of hundreds of thousands of links can take time. Each variant gets
 published as soon as all of its links have been generated. The previous version
@@ -142,8 +148,9 @@ programmatic sitemap generation. These include:
  * setVariants
  * getSitemap
  * removeSitemap
- * generateSitemap
+ * queue
  * rebuildQueue
+ * generateSitemap
  * enableEntityType
  * disableEntityType
  * setBundleSettings
@@ -162,11 +169,7 @@ programmatic sitemap generation. These include:
     * addSitemapVariant
     * removeSitemapVariants
  * getQueueWorker
-    * deleteQueue
-    * rebuildQueue
     * getInitialElementCount
-    * getQueuedElementCount
-    * getStashedResultCount
     * getProcessedElementCount
     * generationInProgress