Merge pull request #1812 from miguelbernadi/issue-1801

Mention includes in configuration section

Author: ben

book/08-customizing-git/sections/config.asc

@@ -47,6 +47,11 @@ $ man git-config
 This command lists all the available options in quite a bit of detail.
 You can also find this reference material at https://git-scm.com/docs/git-config[^].
 
+[NOTE]
+====
+For advanced use cases you may want to look up "Conditional includes" in the documentation mentioned above.
+====
+
 ===== `core.editor`
 
 ((($EDITOR)))((($VISUAL, see $EDITOR)))