move pandas and xarray version limits to constraints.txt

Author: mhidas

constraints.txt

@@ -1 +1,3 @@
-cftime<1.1.1;python_version=='3.5'
+cftime<1.1.1;python_version=='3.5'
+pandas<0.25.0;python_version=='3.5'
+xarray<0.14.0;python_version=='3.5'

setup.py

@@ -4,8 +4,8 @@
     'jsonschema>=2.6.0,<3.0.0',
     'numpy>=1.13.0',
     'netCDF4>=1.5.3',
-    'pandas>=0.24.2,<0.25.0',
-    'xarray>=0.11.3,<0.14.0'
+    'pandas>=0.24.2',
+    'xarray>=0.11.3'
 ]
 
 TESTS_REQUIRE = [