specify versions in requirements

Anton Björklund · Aggrathon · commit 19996e5165d9 · 2021-06-28T12:09:00.000+03:00
diff --git a/requirements.txt b/requirements.txt
@@ -1,5 +1,5 @@
-numpy
-scipy
-PyLBFGS
-numba
-matplotlib
+numpy>=1.19
+scipy>=1.4
+PyLBFGS>=0.2
+numba=>0.53
+matplotlib>=3.3
