API: bump minimum version of pyparsing to 2.0.3

This prevents an inconsistent test environment because packaging 20.1
requires pyparsing >=2.0.2

Picked 2.0.3 as the change log noted that 2.0.3 fixes a major
regression from 2.0.2.

Author: tacaswell

INSTALL.rst

@@ -114,7 +114,7 @@ Matplotlib requires the following dependencies:
 * `dateutil <https://pypi.org/project/python-dateutil>`_ (>= 2.1)
 * `kiwisolver <https://github.com/nucleic/kiwi>`_ (>= 1.0.0)
 * `Pillow <https://pillow.readthedocs.io/en/latest/>`_ (>= 6.2)
-* `pyparsing <https://pyparsing.wikispaces.com/>`_
+* `pyparsing <https://pyparsing.wikispaces.com/>`_ (>=2.0.3)
 
 Optionally, you can also install a number of packages to enable better user
 interface toolkits. See :ref:`what-is-a-backend` for more details on the

requirements/testing/travis36minver.txt

@@ -3,4 +3,4 @@
 cycler==0.10
 python-dateutil==2.1
 numpy==1.15.0
-pyparsing==2.0.1
+pyparsing==2.0.3

setup.py

@@ -262,7 +262,7 @@ def run(self):
             "kiwisolver>=1.0.1",
             "numpy>=1.15",
             "pillow>=6.2.0",
-            "pyparsing>=2.0.1,!=2.0.4,!=2.1.2,!=2.1.6",
+            "pyparsing>=2.0.3,!=2.0.4,!=2.1.2,!=2.1.6",
             "python-dateutil>=2.1",
         ],