Changed to use Pytest as the test runner jpadilla#111

Author: mark-adams

.coveragerc

@@ -1,3 +1,5 @@
 [run]
-append = True
-source = jwt
+omit =
+    tests/*
+    .tox/*
+    setup.py

setup.cfg

@@ -3,3 +3,6 @@ max-line-length = 119
 
 [wheel]
 universal = 1
+
+[pytest]
+addopts = --cov-report term-missing --cov-config=.coveragerc --cov

tox.ini

@@ -3,53 +3,49 @@ envlist = py26, py27, py27-contrib-crypto, py27-nocrypto, py32, py33, py34, py34
 
 [testenv]
 commands =
-    coverage erase
-    coverage run setup.py test
-    coverage report -m
+    py.test .
 deps =
-    cryptography
     unittest2
-    coverage
+    cryptography
+    pytest
+    pytest-cov
 
 [testenv:py34-contrib-crypto]
 basepython = python3.4
 commands =
-    coverage erase
-    coverage run setup.py test
-    coverage report -m
+    py.test .
 deps =
     pycrypto
     ecdsa
-    coverage
+    pytest
+    pytest-cov
+
 
 [testenv:py27-contrib-crypto]
 basepython = python2.7
 commands =
-    coverage erase
-    coverage run setup.py test
-    coverage report -m
+    py.test .
 deps =
     pycrypto
     ecdsa
-    coverage
+    pytest
+    pytest-cov
 
 [testenv:py34-nocrypto]
 basepython = python3.4
 commands =
-    coverage erase
-    coverage run setup.py test
-    coverage report -m
+    py.test .
 deps =
-    coverage
+    pytest
+    pytest-cov
 
 [testenv:py27-nocrypto]
 basepython = python2.7
 commands =
-    coverage erase
-    coverage run setup.py test
-    coverage report -m
+    py.test .
 deps =
-    coverage
+    pytest
+    pytest-cov
 
 [testenv:pep8]
 basepython = python2.7