slight update tutorial

docs/tutorial.rst

@@ -21,12 +21,16 @@ Now, we must download the code base and
 ensure it runs properly; these instructions are implemented via the
 command line.
 Notes: 
+
 1. these instructions are tested for Linux and presumed to work on Mac, but untested on Windows. 
 It is likely some of the underlying software (redis servers) can not be installed on Windows,
 so running on *Windows Subsystem for Linux* is advised. 
 2. Python development tools are required by some packages: 
 if the `pip install -r requirements` fail, here are some `possible solutions 
 <https://stackoverflow.com/questions/21530577/fatal-error-python-h-no-such-file-or-directory>`_.
+3. Here we recommend using a virtual environment to manage the :term:`QMLA` ecosystem; 
+a resource for managing virtual environments is `virtualenvwrapper
+<https://realpython.com/python-virtual-environments-a-primer/>`_. 
 
 
 The steps of preparing the codebase are