Fix pep8 and docs build problems

- fix few pep8 complains
- integrated upper-constraints
- uncapped Sphinx to use upper-constraints cap
- removed deprecated oslosphinx

Change-Id: I1abffe16975e5e2c9ca1059dd866d605b9485bf9

tox.ini

@@ -7,7 +7,8 @@ skipsdist = True
 basepython=python2.7
 setenv =
    VIRTUAL_ENV={envdir}
-deps = -r{toxinidir}/test-requirements.txt
+deps = -c{env:UPPER_CONSTRAINTS_FILE:https://opendev.org/openstack/requirements/raw/branch/master/upper-constraints.txt}
+       -r{toxinidir}/test-requirements.txt
 
 [testenv:venv]
 basepython = python3
@@ -84,4 +85,3 @@ commands=
 whitelist_externals =
   sh
   bash
-