docs: add intersphinx mappings and update library alternatives

examples/tif_hologram.py

@@ -10,9 +10,10 @@
 corresponding `Python example <http://shampoo.readthedocs.io/en/latest
 /getting_started.html#simple-numerical-reconstruction>`_.
 
-The object returned by the `get_qpimage` function is an instance of
-:class:`qpimage.QPImage <qpimage.core.QPImage>` which allows for
-field refocusing. The refocused QPImage is background-corrected
+The object returned by the 
+:func:`get_qpimage <qpformat.file_formats.dataset.SingleData.get_qpimage`
+function is an instance of :class:`qpimage.QPImage <qpimage.core.QPImage>`
+which allows for field refocusing. The refocused QPImage is background-corrected
 using a polynomial fit to the phase data at locations where the
 amplitude data is not attenuated (bright regions in the amplitude
 image).