Updated documentation.

doc/snac.1

@@ -152,7 +152,9 @@ what the administrator defined in the global server settings
 only if it's lesser (i.e. you cannot keep posts for longer
 than what the admin desires). A value of 0 (the default) means
 that the global server settings will apply to the posts in your
-timeline.
+timeline. Also, if the administrator has configured it,
+purged local posts generate a Delete activity and sends it
+everywhere.
 .It Drop direct messages from people you don't follow
 Just what it says in the tin. This is to mitigate spammers
 coming from Fediverse instances with lax / open registration

doc/snac.8

@@ -169,6 +169,9 @@ fill up with old crap and finally burst in flames, you can disable
 purging by setting this to 0.
 .It Ic local_purge_days
 Same as before, but for the user-generated entries in the local timeline.
+.It Ic propagate_local_purge
+If this value is set to true, a Delete activity is generated for every
+local post purged and sent everywhere.
 .It Ic cssurls
 This is a list of URLs to CSS files that will be inserted, in this order,
 in the HTML before the user CSS. Use these files to configure the global