docs: trim some TODO items, and condense several others

Remove the suggested clever bracket matching.

TODO

@@ -1,18 +1,17 @@
 A list of desired features
 --------------------------
 
-Somewhat urgent:
-- Allow color syntaxes to apply to more than just color, so that we can
+* Allow color syntaxes to apply to more than just color, so that we can
   e.g. specify a different alternate spell checker depending on which
   file type we have open.
 
-Vague musings:
-- Add support for right-to-left text (RTL), through FriBidi?
-- Allow setting marks (saved positions, not to be confused with the
+* Add support for right-to-left text (RTL).
+
+* Allow setting bookmarks (saved positions, not to be confused with the
   mark set via Ctrl-^) at various lines and/or columns in the buffer,
   and allow movement between them with a single keystroke?
-- Make matching bracket searches sophisticated enough to skip over
-  brackets inside comments?
+  See https://savannah.gnu.org/bugs/?57577.
+
 
 For version 4.8:
 - Detect when text is being pasted, so that we can handle it faster. [DONE]
@@ -32,8 +31,7 @@ For version 2.8:
 For version 2.4:
 - Handle window resizes better.  After we've resized, we should stay
   wherever we were before we resized, as Pico does. [DONE]
-- Allow even better file-type detection than we have currently, e.g.
-  through libmagic. [DONE]
+- Allow even better file-type detection, e.g. through libmagic. [DONE]
 - Compatibility with vim status files to let other editors know we're
   in a file. [DONE]
 
@@ -50,36 +48,31 @@ For version 2.0:
 - Support for paragraph searches. [DONE]
 - Support for justifying the entire file at once. [DONE]
 - Support for filename searches in the file browser. [DONE]
-- Keystroke to implement "Add next sequence as raw" like vi's ^V. [DONE]
+- A keystroke to implement "Add next sequence as raw", like vi's ^V. [DONE]
 - Spell check selected text only. [DONE]
-- Make "To Line" (^W^T) and "Read from Command" (^R^X) reenter their
-  parent menu when their keystroke is entered a second time (^W^T^T and
-  (^R^X^X) (requires figuring out when to keep cursor position and when
-  not to). [DONE]
-- Fix resetstatuspos global which we shouldn't have. [DONE]
+- Make "To Line" (^W^T) and "Read from Command" (^R^X) return to their parent
+  menu when their keystroke is entered again (^W^T^T and ^R^X^X). [DONE]
 
 For version 1.2:
 - Single-line scroll up/down? [DONE]
-- Color syntax highlighting? (There seems to be a demand for it.) [DONE]
+- Color syntax highlighting? [DONE]
 - Support for a .nanorc file. [DONE]
 - Backup making (filename~)? [DONE]
 - Search/replace string history. [DONE]
-- Implement Pico's -j and -g flags, as they are pretty easy to do. [DONE]
-- Make mouse support work with clicking on the shortcuts (-m). [DONE]
+- Implement Pico's -j and -g flags. [DONE]
+- Make mouse support (-m) work with clicking on the shortcuts. [DONE]
 - Implement -o (--operatingdir, a chroot of sorts). [DONE]
-- Allow -r to take a negative argument, meaning right margin instead of
-  left (allows resizing that way), formerly -W arg. [DONE]
+- Allow -r to take a negative argument. [DONE]
 
 For version 1.0:
 - Implement Spelling. [DONE]
 - Implement Help. [DONE]
 - Internationalization [In progress, translators welcome!]
 - Allow nano to be resized in X. [DONE]
-- On PageUp/Down, put the cursor on the first line (like Pico), not the
-  center line. [DONE]
+- On PageUp/Down, put the cursor on the first screen line (like Pico). [DONE]
 - Implement justify function. [DONE]
 - Cut to end of line. [DONE]
 - Built-in speller command. [DONE]
-- Better statusbar interaction (scrolling, tab completion). [DONE]
+- Better status-bar interaction (scrolling, tab completion). [DONE]
 - Unjustify command (^U after ^J). [DONE]
 - Username completion (~user). [DONE]