Splice in project template

I tried to merge it so that future updates from the template will be
much easier.

The template is hosted at:
https://github.com/ethereum/ethereum-python-project-template

tox.ini

@@ -1,48 +1,58 @@
-# Reference: https://github.com/ethereum/py_ecc/blob/d0da74402210ea1503ef83b3c489d5b5eba7f7bf/tox.ini
+# Reference: https://github.com/ethereum/ethereum-python-project-template/blob/master/tox.ini
 
+# TODO: consider py36 and pypy3 support
 [tox]
 envlist =
     py37-test
     py37-interop
     lint
-
-[flake8]
-max-line-length = 100
-exclude = *_pb2*.py
-ignore = E203, W503
-max-complexity = 18
-select = B,C,E,F,W,T4,B9
+    docs
 
 [isort]
+combine_as_imports=True
 force_sort_within_sections=True
-known_third_party=pytest,p2pclient,pexpect
-multi_line_output=3
 include_trailing_comma=True
-force_grid_wrap=0
-use_parentheses=True
+known_third_party=hypothesis,pytest,p2pclient,pexpect
+known_first_party=<MODULE_NAME>
 line_length=88
+multi_line_output=3
+use_parentheses=True
+force_grid_wrap=0
 skip_glob=
     *_pb2*.py
     *.pyi
 
+[flake8]
+max-line-length = 100
+exclude = venv*,.tox,docs,build,*_pb2*.py
+ignore = E203, W503
+max-complexity = 18
+select = B,C,E,F,W,T4,B9
+
 [testenv]
+usedevelop=True
+commands =
+    test: pytest {posargs:tests/}
+    docs: make build-docs
+basepython =
+    docs: python
+    py37: python3.7
+extras =
+    test
+    docs: doc
+whitelist_externals = make
 deps =
 passenv = CI TRAVIS TRAVIS_*
-extras = test
-commands =
-    test: pytest tests/
-basepython =
-    py37: python3.7
 
 [testenv:lint]
 basepython = python3
-extras = dev
+extras = lint
 commands =
-    mypy -p libp2p -p examples --config-file {toxinidir}/mypy.ini
+    mypy -p {toxinidir}/libp2p -p examples --config-file {toxinidir}/mypy.ini
+    flake8 {toxinidir}/libp2p {toxinidir}/tests tests_interop examples setup.py
     black --check libp2p tests tests_interop examples setup.py
-    isort --recursive --check-only --diff libp2p tests tests_interop examples setup.py
+    isort --recursive --check-only --diff {toxinidir}/libp2p {toxinidir}/tests tests_interop examples setup.py
     docformatter --pre-summary-newline --check --recursive libp2p tests tests_interop examples setup.py
-    flake8 libp2p tests tests_interop examples setup.py
 
 [testenv:py37-interop]
 deps =