[book] fix Session.{set,free}_cnxset autodoc
They're Session methods, not bare functions.
Without this building the docs says:
reading sources... [ 39%] devrepo/repo/sessions
Traceback (most recent call last):
File "/usr/lib/pymodules/python2.7/sphinx/ext/autodoc.py", line 326, in import_object
obj = self.get_attr(obj, part)
File "/usr/lib/pymodules/python2.7/sphinx/ext/autodoc.py", line 232, in get_attr
return safe_getattr(obj, name, *defargs)
File "/usr/lib/pymodules/python2.7/sphinx/util/inspect.py", line 70, in safe_getattr
raise AttributeError(name)
AttributeError: set_cnxset
Traceback (most recent call last):
File "/usr/lib/pymodules/python2.7/sphinx/ext/autodoc.py", line 326, in import_object
obj = self.get_attr(obj, part)
File "/usr/lib/pymodules/python2.7/sphinx/ext/autodoc.py", line 232, in get_attr
return safe_getattr(obj, name, *defargs)
File "/usr/lib/pymodules/python2.7/sphinx/util/inspect.py", line 70, in safe_getattr
raise AttributeError(name)
AttributeError: free_cnxset
# -*- coding: utf-8 -*-
# copyright %(year)s %(author)s, all rights reserved.
# contact %(author-web-site)s -- mailto:%(author-email)s
#
%(long-license)s
"""%(distname)s entity's classes"""