close "Read the Docs apt module page is empty", #48

RTD requires modules relying on Windows-only DLLs etc. be "mocked". It
doesn't need to be able to actually run the code, just process for
docstrings etc.

Initially I thought it was ctypes itself that needed to be mocked, but
it turns out I needed to work closer to home and _mock the module which
calls ctypes_, `knownpaths.py`.

Thank you to @Dunes on Stack Overflow, whose comment I thought was
off-track and not going to help. However it gave just enough of a
turning to my mind and path of investigation to land me in the right
place after all. Not all teachings look like teaching!

http://stackoverflow.com/questions/30950870/mock-import-of-ctypes-fails-with-unsupported-operand-on-read-the-docs

docs/source/conf.py

@@ -16,6 +16,7 @@
 import os
 import shlex
 
+# Read The Docs requires modules relying on Windows-only DLLs etc. be "mocked".
 # https://read-the-docs.readthedocs.org/en/latest/faq.html#i-get-import-errors-on-libraries-that-depend-on-c-modules
 try:
     from unittest.mock import MagicMock #py3 import

docs/source/index.rst.leo

@@ -12,7 +12,7 @@
 <vnodes>
 <v t="maphew.20150613204824.4"><vh>@persistence</vh>
 <v t="maphew.20150613204824.5" a="E"><vh>@data:@auto conf.py</vh>
-<v t="maphew.20150620221605.6"><vh>@gnxs</vh></v>
+<v t="maphew.20150620221605.8"><vh>@gnxs</vh></v>
 </v>
 </v>
 <v t="maphew.20150601230033.5" a="E"><vh>Apt - Read The Docs</vh>
@@ -27,7 +27,7 @@
 <t tx="maphew.20150613204824.4"></t>
 <t tx="maphew.20150613204824.5">gnx: maphew.20150613204824.2
 </t>
-<t tx="maphew.20150620221605.6">gnx: maphew.20150613204824.3
+<t tx="maphew.20150620221605.8">gnx: maphew.20150613204824.3
 unl: conf declarations
 </t>
 </tnodes>