move builtins to their own directory. fix the reference name

Author: nedbat

Doc/library/constants.rst Doc/builtins/constants.rstDoc/library/constants.rst renamed to Doc/builtins/constants.rst

@@ -1,4 +1,4 @@
-.. _builtin-index:
+.. _builtins-index:
 
 #######################
   Built-ins reference

Doc/library/exceptions.rst Doc/builtins/exceptions.rstDoc/library/exceptions.rst renamed to Doc/builtins/exceptions.rst

@@ -381,9 +381,9 @@
         'manual',
     ),
     (
-        'library/builtin-index',
-        'builtin.tex',
-        'Built-in Functions and Classes',
+        'builtins/index',
+        'builtins.tex',
+        'Built-ins Reference',
         _doc_authors,
         'manual',
     ),

Doc/library/functions.rst Doc/builtins/functions.rstDoc/library/functions.rst renamed to Doc/builtins/functions.rst

@@ -8,7 +8,7 @@
    tutorial/index.rst
    using/index.rst
    reference/index.rst
-   library/builtin-index.rst
+   builtins/index.rst
    library/index.rst
    extending/index.rst
    c-api/index.rst

Doc/library/builtin-index.rst Doc/builtins/index.rstDoc/library/builtin-index.rst renamed to Doc/builtins/index.rst

@@ -16,7 +16,7 @@ underlying operating system supports this feature.
 
 This document assumes basic knowledge about C and Python.  For an informal
 introduction to Python, see :ref:`tutorial-index`.  :ref:`reference-index`
-gives a more formal definition of the language.  :ref:`builtin-index` documents
+gives a more formal definition of the language.  :ref:`builtins-index` documents
 the built-in functions and object types, and :ref:`library-index` documents the
 modules (both built-in and written in Python) that give the language its wide
 application range.