Fix requirements.txt

requirements.txt

@@ -13,6 +13,6 @@ django-libsass>=0.7,<1
 django-cors-headers>=2.1.0,<2.2
 python-magic>=0.4.13,<0.5
 pyfcm>=1.4.2,<1.5
-celery>=4.0<4.2
-redis>=2.10<2.11
-django-celery-results>=1.0.1<1.1
+celery>=4.0,<4.2
+redis>=2.10,<2.11
+django-celery-results>=1.0.1,<1.1