patch 9.0.0270: some values of 'path' and 'tags' invalid in the tiny version

Problem:    Some values of 'path' and 'tags' do not work in the tiny version.
Solution:   Graduate the +path_extra feature.

runtime/doc/editing.txt

@@ -1703,8 +1703,6 @@ problem goes away the next day.
 ==============================================================================
 11. File Searching					*file-searching*
 
-{not available when compiled without the |+path_extra| feature}
-
 The file searching is currently used for the 'path', 'cdpath' and 'tags'
 options, for |finddir()| and |findfile()|.  Other commands use |wildcards|
 which is slightly different.

runtime/doc/options.txt

@@ -5949,7 +5949,6 @@ A jump table for the options with a short description can be found at |Q_op|.
 	  "http://www.vim.org" will make ":find index.html" work.
 	- Search upwards and downwards in a directory tree using "*", "**" and
 	  ";".  See |file-searching| for info and syntax.
-	  {not available when compiled without the |+path_extra| feature}
 	- Careful with '\' characters, type two to get one in the option: >
 		:set path=.,c:\\include
 <	  Or just use '/' instead: >
@@ -8001,8 +8000,7 @@ A jump table for the options with a short description can be found at |Q_op|.
 	a directory tree.  See |file-searching|.  E.g., "/lib/**/tags" will
 	find all files named "tags" below "/lib".  The filename itself cannot
 	contain wildcards, it is used as-is.  E.g., "/lib/**/tags?" will find
-	files called "tags?".  {not available when compiled without the
-	|+path_extra| feature}
+	files called "tags?".
 	The |tagfiles()| function can be used to get a list of the file names
 	actually used.
 	If Vim was compiled with the |+emacs_tags| feature, Emacs-style tag

runtime/doc/various.txt

@@ -432,7 +432,8 @@ T  *+num64*		64-bit Number support |Number|
 			check the actual size of a Number.
 m  *+ole*		Win32 GUI only: |ole-interface|
 N  *+packages*		Loading |packages|
-N  *+path_extra*	Up/downwards search in 'path' and 'tags'
+T  *+path_extra*	Up/downwards search in 'path' and 'tags'  Always
+			enabled since 9.0.0270
 m  *+perl*		Perl interface |perl|
 m  *+perl/dyn*		Perl interface |perl-dynamic| |/dyn|
 N  *+persistent_undo*	Persistent undo |undo-persistence|