Exclude the confusing, pleonastic 'sc' abbreviation from their names.

This fixes https://savannah.gnu.org/bugs/?53188

.
Reported-by: Ken Tyler <kent@werple.net.au>

The slash is easier to read than the underscore (which almost
disappears at the bottom of the screen), and easier to type
(no Shift needed on a US keyboard), and it kind of harmonizes
with the ^\ for Replace and the M-/ for End-of-buffer.

And when configured with --enable-tiny --enable-nanorc.

This fixes https://savannah.gnu.org/bugs/?53062.

This addresses https://savannah.gnu.org/bugs/?48992.

In this way a single keystroke can produce a fragment of text or a
series of commands, or a mix of the two.  It is like a prerecorded
macro.

This fulfills https://savannah.gnu.org/bugs/?52931.

This brings it in line with the other three "flip" toggles.

And one for me, for the much changed keyboard stuff.

Also remove an unneeded nulling.

When the palette is getting initialized, it is too late to send any
error messages about the rcfile options to standard error.

This fixes https://savannah.gnu.org/bugs/?52871

.
Reported-by: Brand Huntsman <alpha@qzx.com>
Signed-off-by: Brand Huntsman <alpha@qzx.com>

These three functions are needed only when both linter and speller
are available.

If help is enabled, those functions should be described too,
and if nanorc is enabled, they should both be rebindable.

Each leading tab is converted to two tabs, and any leading four spaces
is converted to one tab.  The intended tab size (for keeping most lines
within 80 columns) is now four.

When unindenting/uncommenting affected the bottom line of the marked
region, keep affecting this line also during subsequent consecutive
indenting/commenting.

This fixes https://savannah.gnu.org/bugs/?52718.

So that Commenting comes closer to the somewhat related Indenting
and Unindenting functions.

Also, make the descriptions for indenting/unindenting more precise.

So they will be found quicker.

Also fold two assignments into one.

The escape sequence "Esc [ Z" is a backtab on most supported terminals,
so make sure convert_sequence() treats it as such.

When the mark is on, instead of letting a <Tab> simply insert a Tab
character at the cursor position, let it indent the marked region.
Original-idea-by: Chris Allegretta <chrisa@asty.org>

When not finding a .nanorc file in the user's home directory, nano will
look for a nanorc file in $XDG_CONFIG_HOME and in the ~/.config/nano/
fallback directory.  And when not finding a .nano/ subdir in the user's
home directory, nano will look for (or create) the history files in
$XDG_DATA_HOME or in the ~/.local/share/nano/ fallback directory.

This is a partial implementation of the XDG Base Directory Specification:
https://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html

,
for the purpose of reducing the clutter in a user's home directory, and
to make it easier to back up just the configuration files.
Signed-off-by: Simon Ochsenreither <simon@ochsenreither.de>
Signed-off-by: Benno Schulenberg <bensberg@telfort.nl>

Suggested-by: Brand Huntsman <alpha@qzx.com>

In the tiny version, do_prompt() will now have an extra NULL
parameter, which will cost maybe twenty extra bytes of code.
That is acceptable when it saves thirty lines in the source.