build: make dependencies more flexible

Author: ifedapoolarewaju

setup.py

@@ -4,7 +4,7 @@
 import transloadit
 
 
-install_requires = ['requests>=2.11.1,<3', 'six==1.10.0', 'tuspy==0.2.2']
+install_requires = ['requests>=2.11.1,<3', 'six>=1.10.0', 'tuspy>=0.2.2']
 
 try:
     import pypandoc