tox: Add pytest-sugar.

Nicer test output FTW!

scripts/dev/ci_run.py

@@ -56,7 +56,9 @@ elif travis_os == 'osx' and testenv == 'py34':
 if testenv == 'eslint':
     subprocess.check_call(['eslint', 'qutebrowser'])
 elif testenv == 'py34' and travis_os == 'linux':
-    subprocess.check_call(['xvfb-run', '-s', '-screen 0 640x480x16',
-                           'tox', '-e', testenv])
+    cmdline = ['xvfb-run', '-s', '-screen 0 640x480x16']
 else:
-    subprocess.check_call(['tox', '-e', testenv])
+    cmdline = []
+
+cmdline += ['tox', '-e', testenv, '--', '-p', 'no:sugar', 'tests']
+subprocess.check_call(cmdline)

tox.ini

@@ -22,6 +22,7 @@ deps =
     pytest-mock==0.8.1
     pytest-html==1.6
     pytest-faulthandler==1.0.1
+    pytest-sugar==0.4.0
     xvfbwrapper==0.2.5
     hypothesis==1.11.4
     coverage==4.0.0