Prepare for 4.21 release #250

CHANGELOG

@@ -1,4 +1,4 @@
-Release 4.21
+2020-05-22 Release 4.21
 	- BACKWARDS-INCOMPATIBLE: rename "whitelist" to "includes" in
 	  hxl.model.Dataset.with_columns() and JSON format for loading a
 	  ColumnFilter

hxl/__init__.py

@@ -45,7 +45,7 @@
 if sys.version_info < (3,):
     raise RuntimeError("libhxl requires Python 3 or higher")
 
-__version__="4.20"
+__version__="4.21"
 """Module version number
 see https://www.python.org/dev/peps/pep-0396/
 """

setup.py

@@ -11,14 +11,23 @@
 
 setup(
     name='libhxl',
-    version="4.20",
+    version="4.21",
     description='Python support library for the Humanitarian Exchange Language (HXL). See http://hxlstandard.org and https://github.com/HXLStandard/libhxl-python',
     long_description=long_description,
     long_description_content_type="text/markdown",
     author='David Megginson',
     author_email='[email protected]',
     url='http://hxlproject.org',
-    install_requires=['python-dateutil', 'xlrd', 'requests', 'requests_cache', 'unidecode', 'python-io-wrapper>=0.2', 'jsonpath_ng', 'ply'],
+    install_requires=[
+        'requests>=2.11',
+        'requests_cache',
+        'python-dateutil',
+        'xlrd',
+        'unidecode',
+        'python-io-wrapper>=0.2',
+        'jsonpath_ng',
+        'ply'
+    ],
     packages=['hxl', 'hxl.formulas'],
     package_data={'hxl': ['*.json']},
     include_package_data=True,