Drop Python 3.4 support

Python 3.4's end of life is 2019-03-16 and Debian stable provides 3.5.3.

Author: liZe

.travis.yml

@@ -3,8 +3,6 @@ sudo: false
 
 matrix:
   include:
-    - os: linux
-      python: 3.4
     - os: linux
       python: 3.5
     - os: linux

setup.cfg

@@ -27,7 +27,6 @@ classifiers =
   License :: OSI Approved :: GNU Lesser General Public License v3 or later (LGPLv3+)
   Operating System :: OS Independent
   Programming Language :: Python :: 3 :: Only
-  Programming Language :: Python :: 3.4
   Programming Language :: Python :: 3.5
   Programming Language :: Python :: 3.6
   Programming Language :: Python :: 3.7
@@ -49,7 +48,7 @@ tests_require =
   pytest-flake8
   pytest-isort
   pytest-runner
-python_requires = >= 3.4
+python_requires = >= 3.5
 
 [options.entry_points]
 console-scripts =