Doc update for previous symbol table changes.

Related to #183.

Author: tzlaine

doc/tutorial.qbk

@@ -1126,24 +1126,12 @@ the second `'X'` is recognized by the symbol table parser.  However:
 
 If we parse again, we find that `"X"` did not stay in the symbol table.  The
 fact that `symbols` was declared const might have given you a hint that this
-would happen.  Also, notice that the call to `insert()` in the semantic action
-uses the parse context; that's where all the symbol table changes are stored
-during the parse.
+would happen.
 
 The full program:
 
 [self_filling_symbol_table_example]
 
-[tip _symbols_ also has a call operator that does exactly what
-`.insert_for_next_parse()` does.  This allows you to chain additions with a
-convenient syntax, like this:
-
-```
-    symbols<int> roman_numerals;
-    roman_numerals.insert_for_next_parse("I", 1)("V", 5)("X", 10);
-```
-]
-
 [important _symbols_ stores all its strings in UTF-32 internally.  If you do
 Unicode or ASCII parsing, this will not matter to you at all.  If you do
 non-Unicode parsing of a character encoding that is not a subset of Unicode
@@ -1163,6 +1151,11 @@ erase and clear for the current parse, and another that applies only to
 subsequent parses.  The full set of operations can be found in the _symbols_
 API docs.
 
+[mpte There are two versions of each of the _symbols_ `*_for_next_parse()`
+functions _emdash_ one that takes a context, and one that does not.  The one
+with the context is meant to be used within a semantic action.  The one
+without the context is for use outside of any parse.]
+
 [endsect]
 
 [section The Parsers And Their Uses]