title: include imported functions in module documentation
body: <p>My code has the following directory structure:</p>
  
  <pre><code>apkg/
    __init__.py
    amod.py
    bmod.py
    cmod.py
  </code></pre>
  
  <p>Where <code>apkg/__init__.py</code> contains:</p>
  
  <pre><code>"""
  effusive top-level documentation
  """
  from apkg.amod import foo
  from apkg.bmod import bar
  from apkg.cmod import baz
  </code></pre>
  
  <p>And from the python repl I can successfully invoke <code>foo</code>, <code>bar</code>, and <code>baz</code> without knowing which submodule they're defined in:</p>
  
  <pre><code>&gt;&gt;&gt; import apkg
  &gt;&gt;&gt; apkg.foo()
  "foo"
  </code></pre>
  
  <p>And get their documentation:</p>
  
  <pre><code>&gt;&gt;&gt; help(apkg.foo)
  Help on function foo in module apkg.amod:
  
  foo()
      Returns "foo"
  </code></pre>
  
  <p>But they're not advertised in <code>apkg</code>'s documentation:</p>
  
  <pre><code>&gt;&gt;&gt; help(apkg)
  Help on package apkg:
  
  NAME
      apkg - effusive top-level documentation
  
  PACKAGE CONTENTS
      amod
      bmod
      cmod
  
  FILE
      /path/to/apkg/__init__.py
  </code></pre>
  
  <p>This makes sense as a default, since I'd hardly want to include <code>defaultdict</code>'s documentation just by doing <code>from collections import defaultdict</code> in <code>apkg/__init__.py</code>.</p>
  
  <p>Is there a way to override this default, so I can tell the documentation parser to list <code>foo</code>, <code>bar</code> and <code>baz</code> in the FUNCTIONS section for <code>help(apkg)</code>?</p>