[Doc] Cannot Build Docs on 2016.3 or Develop Branch

[rallytime]

Description of Issue/Question

When attempting to fix a documentation issue, I realized the changes weren't present on the live docs site. I tried to build the docs manually, but it errors and exits. Here's the error from the develop branch, but the same thing happens on 2016.3 as well:

# make html
No need to update translations. Skipping...
sphinx-build -b html -d _build/doctrees    . _build/html
Running Sphinx v1.3.5
loading translations [en]... done
loading pickled environment... done
[autosummary] generating autosummary for: contents.rst, faq.rst, glossary.rst, ref/auth/all/index.rst, ref/auth/all/salt.auth.auto.rst, ref/auth/all/salt.auth.django.rst, ref/auth/all/salt.auth.keystone.rst, ref/auth/all/salt.auth.ldap.rst, ref/auth/all/salt.auth.mysql.rst, ref/auth/all/salt.auth.pam.rst, ..., topics/tutorials/walkthrough_macosx.rst, topics/tutorials/writing_tests.rst, topics/using_salt.rst, topics/virt/disk.rst, topics/virt/index.rst, topics/virt/nic.rst, topics/windows/index.rst, topics/windows/windows-package-manager.rst, topics/windows/windows-specific-behavior.rst, topics/yaml/index.rst

Exception occurred:
  File "/root/SaltStack/salt/salt/config/__init__.py", line 88, in _gather_buffer_space
    return max([total_mem * 0.05, 10 << 20])
TypeError: unsupported operand type(s) for *: 'Mock' and 'float'
The full traceback has been saved in /tmp/sphinx-err-7_MJFa.log, if you want to report the issue to the developers.
Please also report this if it was a user error, so that a better error message can be provided next time.
A bug report can be filed in the tracker at <https://github.com/sphinx-doc/sphinx/issues>. Thanks!
make: *** [html] Error 1

And the full stacktrace from the logs looks like this:

 Sphinx version: 1.3.5
# Python version: 2.7.6 (CPython)
# Docutils version: 0.12 release
# Jinja2 version: 2.8
# Last messages:

# Loaded extensions:
Traceback (most recent call last):
  File "/usr/local/lib/python2.7/dist-packages/sphinx/cmdline.py", line 243, in main
    opts.warningiserror, opts.tags, opts.verbosity, opts.jobs)
  File "/usr/local/lib/python2.7/dist-packages/sphinx/application.py", line 189, in __init__
    self._init_builder(self.buildername)
  File "/usr/local/lib/python2.7/dist-packages/sphinx/application.py", line 252, in _init_builder
    self.emit('builder-inited')
  File "/usr/local/lib/python2.7/dist-packages/sphinx/application.py", line 508, in emit
    results.append(callback(self, *args))
  File "/usr/local/lib/python2.7/dist-packages/sphinx/ext/autosummary/__init__.py", line 564, in process_generate_options
    base_path=app.srcdir)
  File "/usr/local/lib/python2.7/dist-packages/sphinx/ext/autosummary/generate.py", line 115, in generate_autosummary_docs
    items = find_autosummary_in_files(sources)
  File "/usr/local/lib/python2.7/dist-packages/sphinx/ext/autosummary/generate.py", line 228, in find_autosummary_in_files
    filename=filename))
  File "/usr/local/lib/python2.7/dist-packages/sphinx/ext/autosummary/generate.py", line 326, in find_autosummary_in_lines
    current_module, filename=filename))
  File "/usr/local/lib/python2.7/dist-packages/sphinx/ext/autosummary/generate.py", line 238, in find_autosummary_in_docstring
    real_name, obj, parent, modname = import_by_name(name)
  File "/usr/local/lib/python2.7/dist-packages/sphinx/ext/autosummary/__init__.py", line 473, in import_by_name
    obj, parent, modname = _import_by_name(prefixed_name)
  File "/usr/local/lib/python2.7/dist-packages/sphinx/ext/autosummary/__init__.py", line 489, in _import_by_name
    __import__(modname)
  File "/root/SaltStack/salt/salt/auth/__init__.py", line 30, in <module>
    import salt.config
  File "/root/SaltStack/salt/salt/config/__init__.py", line 92, in <module>
    _DFLT_IPC_WBUFFER = _gather_buffer_space() * .5
  File "/root/SaltStack/salt/salt/config/__init__.py", line 88, in _gather_buffer_space
    return max([total_mem * 0.05, 10 << 20])
TypeError: unsupported operand type(s) for *: 'Mock' and 'float'

The docs haven't been building in this manner since #34683 was merged.

Versions Report

# salt --versions
Salt Version:
           Salt: 2016.3.0-1142-gb570613

Dependency Versions:
           cffi: 0.8.6
       cherrypy: 5.0.1
       dateutil: 2.4.2
          gitdb: 0.6.4
      gitpython: 1.0.1
          ioflo: 1.5.5
         Jinja2: 2.8
        libgit2: Not Installed
        libnacl: Not Installed
       M2Crypto: 0.21.1
           Mako: Not Installed
   msgpack-pure: Not Installed
 msgpack-python: 0.4.6
   mysql-python: 1.2.3
      pycparser: 2.10
       pycrypto: 2.6.1
         pygit2: Not Installed
         Python: 2.7.6 (default, Jun 22 2015, 17:58:13)
   python-gnupg: 0.3.8
         PyYAML: 3.10
          PyZMQ: 14.5.0
           RAET: Not Installed
          smmap: 0.9.0
        timelib: 0.2.4
        Tornado: 4.2.1
            ZMQ: 4.0.5

System Versions:
           dist: Ubuntu 14.04 trusty
        machine: x86_64
        release: 4.5.5-x86_64-linode69
         system: Linux
        version: Ubuntu 14.04 trusty

ping @jacobhammons

[bdrung]

I ran into the same issue when I tried to package 2016.3.2 for Debian.

[meggiebot]

Fixed here: #35729

[meggiebot]

@cachedout looks like this might need some additional work

[rallytime]

Fixed by #35763