NFC: switch setup.py to use requirements txt

Author: Charlotte Godley

setup.py

@@ -4,6 +4,9 @@
 with open("README.md", "r") as fh:
     long_description = fh.read()
 
+with open('requirements.txt') as f:
+    required = f.read().splitlines()
+
 setuptools.setup(
     name="dotscience",
     version=__version__,
@@ -14,7 +17,7 @@
     long_description_content_type="text/markdown",
     url="https://github.com/dotmesh-io/dotscience-python",
     packages=setuptools.find_packages(),
-    install_requires=['datadots-api>=0.2.1', 'requests'],
+    install_requires=required,
     tests_require=['pytest', 'hypothesis', 'datadots-api>=0.2.1'],
     zip_safe=True,
     classifiers=[