Colapse text by Tab indent in docs would be nice

Colapse text by Tab indent in docs would be nice

it would be nice to get a additional border in the editor with the + / - wigns to colapse text by tab level...

Title
----blah
Title 2
----blah
--------blah

would look colapsed as
+Title
+Title 2

or
+Title
-Title2
+----Blah

that would be very great :)

thanks