Add zola check to changelog and remove check option from config doc

CHANGELOG.md

@@ -9,6 +9,7 @@
 ### Other
 
 - Fix image processing not happening if called from the template
+- Add a `zola check` command to that validates the site and checks all external links
 
 ## 0.7.0 (2019-04-28)
 

docs/content/documentation/getting-started/configuration.md

@@ -67,12 +67,6 @@ compile_sass = false
 # content for the `default_language`
 build_search_index = false
 
-# Go through every links in all content and check if the links are valid
-# If a link is invalid (404, 500, etc), the build will error.
-# Link checking can take a very long time if you have many links so this should
-# only enabled once in a while to catch any dead links.
-check_external_links = false
-
 # A list of glob patterns specifying asset files to ignore when
 # processing the content directory.
 # Defaults to none, which means all asset files are copied over to the public folder.