fixed markup errors

Doc/library/readline.rst

@@ -14,7 +14,7 @@ made using  this module affect the behaviour of both the interpreter's
 interactive prompt  and the prompts offered by the :func:`raw_input` and
 :func:`input` built-in functions.
 
-..note::
+.. note::
 
   On MacOS X the :mod:`readline` module can be implemented using
   the ``libedit`` library instead of GNU readline.

Doc/library/runpy.rst

@@ -45,7 +45,7 @@ The :mod:`runpy` module provides two functions:
 
    ``__file__`` is set to the name provided by the module loader. If the
    loader does not make filename information available, this variable is set
-   to `:const:`None`.
+   to :const:`None`.
 
    ``__loader__`` is set to the PEP 302 module loader used to retrieve the
    code for the module (This loader may be a wrapper around the standard

Doc/whatsnew/2.7.rst

@@ -750,7 +750,7 @@ changes, or look through the Subversion logs for all the details.
   global site-packages directories, and
   :func:`getusersitepackages` returns the path of the user's
   site-packages directory.
-  :func:`getuserbase` returns the value of the :envvar:``USER_BASE``
+  :func:`getuserbase` returns the value of the :envvar:`USER_BASE`
   environment variable, giving the path to a directory that can be used
   to store data.
   (Contributed by Tarek Ziade; :issue:`6693`.)