Lisp Reference Manual: Index standard symbol properties.

Lisp Reference Manual: Index standard symbol properties.

* doc/lispref/symbols.texi (Standard Properties):
* doc/lispref/commands.texi:
* doc/lispref/customize.texi (Variable Definitions):
* doc/lispref/help.texi:
* doc/lispref/keymaps.texi:
* doc/lispref/minibuf.texi (Minibuffer History):
* doc/lispref/modes.texi (Setting Hooks):
* doc/lispref/sequences.texi (Char-Tables):
* doc/lispref/text.texi (Undo):
* doc/lispref/variables.texi: Each standard symbol property has exactly
one index entry, uniformly formatted as "(symbol property)".

(cherry picked from commit c98d9e8bf58c75e3ed6c7d2f9c5e63fc17bf9cf7)