Cleanup py27 support

Make a few cleanups:
- Remove python 2.7 stanza from setup.py
- Add requires on python >= 3.6 to setup.cfg so that pypi and pip
  know about the requirement
- Remove obsolete sections from setup.cfg:
  * Wheel is not needed for python 3 only repo
  * Some other sections are obsolete
- Update classifiers
- Update requirements, no need for python_version anymore

Change-Id: I4b236a3b85f37358ff44a8063dfec1e4d10c036a

doc/requirements.txt

@@ -1,5 +1,5 @@
 # doc build requirements
-sphinx!=1.6.6,!=1.6.7,!=2.1.0,>=1.6.2;python_version>='3.4' # BSD
+sphinx!=1.6.6,!=1.6.7,!=2.1.0,>=1.6.2 # BSD
 sphinxcontrib-httpdomain>=1.3.0 # BSD
 reno>=2.5.0 # Apache-2.0
 openstackdocstheme>=1.20.0 # Apache-2.0

setup.cfg

@@ -3,9 +3,10 @@ name = yaql
 summary = YAQL - Yet Another Query Language
 description-file =
     README.rst
-author = Stan Lagun
+author = OpenStack
-author-email = slagun@mirantis.com
+author-email = openstack-discuss@lists.openstack.org
 home-page = http://yaql.readthedocs.io
+python-requires = >=3.6
 classifier =
     Environment :: OpenStack
     Intended Audience :: Information Technology
@@ -13,6 +14,8 @@ classifier =
     License :: OSI Approved :: Apache Software License
     Operating System :: POSIX :: Linux
     Programming Language :: Python
+    Programming Language :: Python :: Implementation :: CPython
+    Programming Language :: Python :: 3 :: Only
     Programming Language :: Python :: 3
     Programming Language :: Python :: 3.6
     Programming Language :: Python :: 3.7
@@ -21,14 +24,6 @@ classifier =
 packages =
     yaql
 
-[build_sphinx]
-source-dir = doc/source
-build-dir = doc/build
-all_files = 1
-
-[upload_sphinx]
-upload-dir = doc/build/html
-
 [compile_catalog]
 directory = yaql/locale
 domain = yaql

setup.py

@@ -14,7 +14,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-# THIS FILE IS MANAGED BY THE GLOBAL REQUIREMENTS REPO - DO NOT EDIT
 import setuptools
 
 setuptools.setup(