Cleanup requirements.txt so we don't have to maintain separate copies for py2 and py3.

Signed-off-by: Daniel Nephin <dnephin@gmail.com>

tox.ini

@@ -5,6 +5,8 @@ envlist = py27,py34,pre-commit
 usedevelop=True
 passenv =
     LD_LIBRARY_PATH
+setenv =
+    HOME=/tmp
 deps =
     -rrequirements.txt
 commands =
@@ -19,26 +21,16 @@ commands =
     pre-commit install
     pre-commit run --all-files
 
-[testenv:py26]
-deps =
-    {[testenv]deps}
-    -rrequirements-dev-py2.txt
-
 [testenv:py27]
-deps = {[testenv:py26]deps}
-
-[testenv:pypy]
-deps = {[testenv:py26]deps}
-
-[testenv:py33]
 deps =
     {[testenv]deps}
-    -rrequirements-dev-py3.txt
+    -rrequirements-dev.txt
 
 [testenv:py34]
-deps = {[testenv:py33]deps}
-
-# TODO pypy3
+deps =
+    {[testenv]deps}
+    flake8
+    nose
 
 [flake8]
 # ignore line-length for now