Use py.test as the test runner

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

tox.ini

@@ -8,10 +8,14 @@ passenv =
 setenv =
     HOME=/tmp
 deps =
-    -rrequirements.txt
+    -rrequirements-dev.txt
 commands =
-    nosetests -v --with-coverage --cover-branches --cover-package=compose --cover-erase --cover-html-dir=coverage-html --cover-html {posargs}
-    flake8 compose tests setup.py
+    py.test -v \
+        --cov=compose \
+        --cov-report html \
+        --cov-report term \
+        --cov-config=tox.ini \
+        {posargs}
 
 [testenv:pre-commit]
 skip_install = True
@@ -21,16 +25,16 @@ commands =
     pre-commit install
     pre-commit run --all-files
 
-[testenv:py27]
-deps =
-    {[testenv]deps}
-    -rrequirements-dev.txt
+# Coverage configuration
+[run]
+branch = True
 
-[testenv:py34]
-deps =
-    {[testenv]deps}
-    flake8
-    nose
+[report]
+show_missing = true
+
+[html]
+directory = coverage-html
+# end coverage configuration
 
 [flake8]
 # Allow really long lines for now