tox: Cleanup

Reduce indentation to 2 spaces, remove unused targets, and run
everything under Python 3 by default.

Signed-off-by: Stephen Finucane <stephen@that.guru>

Author: stephenfin

tox.ini

@@ -1,41 +1,42 @@
 [tox]
-minversion = 2.0
-envlist = pep8,mypy,py{27,35,36,37,py}
+minversion = 3.1
+envlist = pep8,mypy,clean,py{27,35,36,37,py},report
+ignore_basepython_conflict = true
 
 [testenv]
+basepython = python3
 deps =
-    -r{toxinidir}/requirements.txt
-    -r{toxinidir}/test-requirements.txt
+  -r{toxinidir}/test-requirements.txt
 commands =
-    pytest -Wall {posargs}
+  pytest -Wall {posargs}
 
 [testenv:pep8]
 deps =
-    flake8
+  flake8
 commands =
-    flake8 {posargs} git_pw
+  flake8 {posargs} git_pw
 
 [testenv:mypy]
 deps=
-    mypy
+  mypy
 commands=
-    mypy {posargs:--ignore-missing-imports --follow-imports=skip} git_pw
+  mypy {posargs:--ignore-missing-imports --follow-imports=skip} git_pw
 
 [testenv:docs]
 deps =
-    -r{toxinidir}/docs/requirements.txt
+  -r{toxinidir}/docs/requirements.txt
 commands =
-    sphinx-build {posargs:-E -W} docs docs/_build/html
+  sphinx-build {posargs:-E -W} docs docs/_build/html
 
 [testenv:man]
 deps =
-    -r{toxinidir}/docs/requirements.txt
+  -r{toxinidir}/docs/requirements.txt
 commands =
-    python setup.py --command-packages=click_man.commands man_pages
+  python setup.py --command-packages=click_man.commands man_pages
 
 [flake8]
-show-source = True
+show-source = true
 
 [travis]
 python =
-    3.7: py37, pep8, mypy
+  3.7: py37, pep8, mypy