Fix tox config:

- make output more colorful
- fix coverage computation (otherwise it fails)
- fix flake8 check which failed when there was no parts dir

.gitignore

@@ -3,6 +3,7 @@ build
 coverage
 develop
 dist
+flake8
 htmlcov
 lib
 parts

tox.ini

@@ -11,14 +11,14 @@ envlist =
 commands =
     {envbindir}/buildout -c {toxinidir}/buildout.cfg buildout:directory={envdir} buildout:develop={toxinidir} bootstrap
     {envbindir}/buildout -c {toxinidir}/buildout.cfg buildout:directory={envdir} buildout:develop={toxinidir} install test
-    coverage run {envbindir}/test
+    coverage run {envbindir}/test {posargs:-cv}
 skip_install = true
 deps =
     setuptools==33.1.1
     zc.buildout
     coverage
 setenv =
-    COVERAGE_FILE=.coverage
+    COVERAGE_FILE=.coverage.{envname}
 
 [testenv:coverage]
 basepython = python2.7
@@ -39,4 +39,4 @@ deps =
     flake8-html
     flake8-debugger
 commands =
-    flake8 --format=html --htmldir={toxinidir}/parts/flake8 --doctests src tests setup.py {posargs}
+    flake8 --format=html --htmldir={toxinidir}/flake8 --doctests src tests setup.py {posargs}