runtime(netrw): upstream snapshot of v176

relevant commits:
- deprecate!: netrw#Launch, netrw#Open and gx mappings
- refactor: move some utility functions in a private file
- feat: add function to deprecate features
- refactor!: remove NetrwClean command and function
- refactor: use appropriate directories to store temporary files
- refactor: better way to call vim.ui.open
- refactor(Open): prefer lua wrapper function instead of cmdline
- refactor!: drop vim 7 checks
- refactor: use vim.ui.open when using neovim
- refactor: remove s:CheckIfKde
- refactor: balloon functionality
- refactor!: remove netrw#Access function

closes: #16519

Signed-off-by: Luca Saccarola <github.e41mv@aleeas.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

runtime/pack/dist/opt/netrw/doc/netrw.txt

@@ -59,7 +59,6 @@ Copyright: Copyright (C) 2017 Charles E Campbell    *netrw-copyright*
       Changing local-only File Permission.................|netrw-gp|
       Changing To A Predecessor Directory.................|netrw-u|
       Changing To A Successor Directory...................|netrw-U|
-      Customizing Browsing With A Special Handler.........|netrw-x|
       Deleting Bookmarks..................................|netrw-mB|
       Deleting Files Or Directories.......................|netrw-D|
       Directory Exploring Commands........................|netrw-explore|
@@ -1110,7 +1109,7 @@ QUICK REFERENCE: MAPS				*netrw-browse-maps* {{{2
 	   U	Change to subsequently-visited directory             |netrw-U|
 	   v	Enter the file/directory under the cursor in a new   |netrw-v|
 		browser window.  A vertical split is used.
-	   x	View file with an associated program. (see |:Open|)
+	   x	View file with an associated program                 |:Open|
 	   X	Execute filename under cursor via |system()|           |netrw-X|
 
 	   %	Open a new file in netrw's current directory         |netrw-%|
@@ -1137,7 +1136,6 @@ QUICK REFERENCE: MAPS				*netrw-browse-maps* {{{2
 
 				*netrw-quickcom* *netrw-quickcoms*
 QUICK REFERENCE: COMMANDS	*netrw-explore-cmds* *netrw-browse-cmds* {{{2
-     :NetrwClean[!]............................................|netrw-clean|
      :NetrwSettings............................................|netrw-settings|
      :Ntree....................................................|netrw-ntree|
      :Explore[!]  [dir] Explore directory of current file......|netrw-explore|
@@ -1450,20 +1448,6 @@ The "gn" map will take the word below the cursor and use that for
 changing the top of the tree listing.
 
 
-NETRW CLEAN					*netrw-clean* *:NetrwClean* {{{2
-
-With :NetrwClean one may easily remove netrw from one's home directory;
-more precisely, from the first directory on your |'runtimepath'|.
-
-With :NetrwClean!, netrw will attempt to remove netrw from all directories on
-your |'runtimepath'|.  Of course, you have to have write/delete permissions
-correct to do this.
-
-With either form of the command, netrw will first ask for confirmation
-that the removal is in fact what you want to do.  If netrw doesn't have
-permission to remove a file, it will issue an error message.
-
-							*netrw-curdir*
 DELETING BOOKMARKS					*netrw-mB* {{{2
 
 To delete a bookmark, use >
@@ -2510,6 +2494,7 @@ your browsing preferences.  (see also: |netrw-settings|)
 				(the capital g:Netrw... is required its
 				holding a function reference)
 
+
   *g:netrw_ctags*		="ctags"
 				The default external program used to create
 				tags
@@ -2913,14 +2898,6 @@ your browsing preferences.  (see also: |netrw-settings|)
 				such as listing, file removal, etc.
 				 default: ssh
 
- *g:netrw_suppress_gx_mesg*	=1 : browsers sometimes produce messages
-				which are normally unwanted intermixed
-				with the page.
-				However, when using links, for example,
-				those messages are what the browser produces.
-				By setting this option to 0, netrw will not
-				suppress browser messages.
-
   *g:netrw_tmpfile_escape*	=' &;'
 				escape() is applied to all temporary files
 				to escape these characters.