Remove future from py3 tests

Author: NathanielRN

setup.py

@@ -1,8 +1,7 @@
-import sys
-
 from setuptools import setup, find_packages
 from os import path
 from aws_xray_sdk.version import VERSION
+from aws_xray_sdk.core.utils.compat import PY2
 
 CURRENT_DIR = path.abspath(path.dirname(__file__))
 
@@ -20,7 +19,7 @@
     'botocore>=1.11.3',
 ]
 
-if sys.version_info[0] == 2:
+if PY2:
     INSTALL_REQUIRED_DEPS.append("future")
 
 setup(

tox.ini

@@ -52,12 +52,12 @@ deps =
     codecov
 
     ; Packages common to all test environments
-    future
     wrapt
 
     ; Python 2.7 only deps
     py{27}: enum34
     py{27}: mock
+    py{27}: future
 
     ; Python 3.4 only deps
     py34: typing >= 3.7.4.3