Numpy requirement changed to allow numba to be used

Author: mikeWShef

requirements_dev.txt

@@ -1,20 +1,20 @@
 sympy
 scikit-image
 matplotlib
-numpy>=1.16.1
+numpy<1.21,>=1.17
 scipy
 numba>=0.48.0
-pip==19.2.3
+wheel>=0.33.6
+flake8>=3.7.8
+pyfftw
+tinydb
+
 bump2version==0.5.11
-wheel==0.33.6
-watchdog==0.9.0
 flake8==3.7.8
 tox==3.14.0
 coverage==4.5.4
 Sphinx==1.8.5
 twine==1.14.0
-pyfftw
-tinydb
 
 pytest==4.6.5
 pytest-runner==5.1