Replace Fedora build instructions with generic ones

Remove the Fedora build instructions. Nobody in the team currently uses
Fedora and can check the instructions.

Provide generic instructions based on pip instead.

Author: pdebuyl

CONTRIBUTING.rst

@@ -46,6 +46,9 @@ to build the SciPy lecture notes, can be inferred from the
 .. literalinclude:: requirements.txt
     :start-after: # libraries before the special comment marked
 
+The installation instructions below cover (i) Debian/Ubuntu with miniconda as this is the
+method we use to test and build the material and (ii) generic instructions using pip.
+
 .. topic:: **Building on Debian/Ubuntu**
 
     The environment needed to create an html version of the SciPy lecture notes
@@ -94,13 +97,19 @@ to build the SciPy lecture notes, can be inferred from the
     SciPy as explained above. Generating a pdf version requires the system packages
     ``texlive``, ``texlive-latex-extra``, ``texlive-fonts-extra``, and ``latexmk``.
 
-.. topic:: **Building on Fedora**
+.. topic:: **Installing the Python packages with pip**
+
+    `pip <https://pip.pypa.io/>`_ is the recommended tool to install Python
+    packages. However, a number of packages must be installed from the system. Install
+    Python, the Python "headers" (the `python3-dev` package on Debian, for instance), a C
+    development environment, `GNU Make <https://www.gnu.org/software/make/>`_, a full LaTeX
+    distribution (e.g. `TeX Live <https://www.tug.org/texlive/>`_ with extra fonts and
+    utilities) and `git <https://git-scm.com/>`_.
+
+    The remaining software can be installed with `pip`. Depending on the configuration, the
+    probably most convenient and safe way to proceed is with::
 
-    As root::
+        pip install --user -r requirements.txt
 
-        yum install python make python-matplotlib texlive-pdfjam texlive scipy \ 
-        texlive-framed texlive-threeparttable texlive-wrapfig texlive-multirow
-        pip install Sphinx
-        pip install Cython
-        pip install scikit-learn
-        pip install scikit-image
+    This will install the software in a local directory belonging to the user and will not
+    interfere with system-wide Python packages.