docs, remove 'guifontset' #11708

- remove redundant autocmd list
  This "grouped" list is useless, it only gets in the way when searching
  for event names.
- intro.txt: cleanup
- starting.txt: update, revisit
- doc: `:help bisect`
- mbyte.txt: update aliases 1656367b90. closes #11960
- options: remove 'guifontset'. Why:
  - It is complicated and is used by almost no one.
  - It is unlikely to be implemented by Nvim GUIs (complicated to parse,
    specific to Xorg...).

src/nvim/api/vim.c

@@ -204,9 +204,9 @@ Integer nvim_get_hl_id_by_name(String name)
 ///
 /// On execution error: does not fail, but updates v:errmsg.
 ///
-///  If you need to input sequences like <C-o> use |nvim_replace_termcodes|
-///  to replace the termcodes and then pass the resulting string to
-///  nvim_feedkeys. You'll also want to enable escape_csi.
+/// If you need to input sequences like <C-o> use |nvim_replace_termcodes| to
+/// replace the termcodes and then pass the resulting string to nvim_feedkeys.
+/// You'll also want to enable escape_csi.
 ///
 /// Example:
 /// <pre>

src/nvim/option_defs.h

@@ -453,7 +453,6 @@ EXTERN char_u   *p_header;      // 'printheader'
 EXTERN int p_prompt;            // 'prompt'
 EXTERN char_u   *p_guicursor;   // 'guicursor'
 EXTERN char_u   *p_guifont;     // 'guifont'
-EXTERN char_u   *p_guifontset;  // 'guifontset'
 EXTERN char_u   *p_guifontwide;  // 'guifontwide'
 EXTERN char_u   *p_hf;          // 'helpfile'
 EXTERN long p_hh;               // 'helpheight'

src/nvim/options.lua

@@ -1021,15 +1021,6 @@ return {
       redraw={'ui_option'},
       defaults={if_true={vi=""}}
     },
-    {
-      full_name='guifontset', abbreviation='gfs',
-      type='string', list='onecomma', scope={'global'},
-      deny_duplicates=true,
-      vi_def=true,
-      varname='p_guifontset',
-      redraw={'ui_option'},
-      defaults={if_true={vi=""}}
-    },
     {
       full_name='guifontwide', abbreviation='gfw',
       type='string', list='onecomma', scope={'global'},

src/nvim/os/time.c

@@ -56,6 +56,8 @@ uint64_t os_now(void)
 
 /// Sleeps for `ms` milliseconds.
 ///
+/// @see uv_sleep() (libuv v1.34.0)
+///
 /// @param ms          Number of milliseconds to sleep
 /// @param ignoreinput If true, only SIGINT (CTRL-C) can interrupt.
 void os_delay(uint64_t ms, bool ignoreinput)
@@ -72,6 +74,8 @@ void os_delay(uint64_t ms, bool ignoreinput)
 
 /// Sleeps for `us` microseconds.
 ///
+/// @see uv_sleep() (libuv v1.34.0)
+///
 /// @param us          Number of microseconds to sleep.
 /// @param ignoreinput If true, ignore all input (including SIGINT/CTRL-C).
 ///                    If false, waiting is aborted on any input.