Make static doc more modular & less duplicated, fix for readthedoc

tox.ini

@@ -12,6 +12,7 @@ envlist =
 
 [testenv]
 deps =
+    -r{toxinidir}/requirements.txt
     -r{toxinidir}/requirements_test.txt
 commands =
     /usr/bin/env SECRET_KEY=test pytest --ds=my_api.config.common --doctest-modules -v --cov my_api/rest --cov-report term-missing
@@ -20,6 +21,7 @@ commands =
 changedir=docs
 #basepython=python3.6
 deps =
+    -r{toxinidir}/requirements.txt
     -r{toxinidir}/requirements_test.txt
 commands=
     sphinx-build -b html -c {envtmpdir}/../../.. -d {envtmpdir}/doctrees . {envtmpdir}/html
@@ -28,6 +30,7 @@ commands=
 skip_install = True
 whitelist_externals = pep8
 deps =
+    -r{toxinidir}/requirements.txt
     -r{toxinidir}/requirements_test.txt
 commands =
     pycodestyle --max-line-length 95 my_api