Fix Python 2.7 install and .travis configuration file issue.

[jgspiro]

Fix for installing Slycot in a Python 2.7 environment - unupported ConfigParser functionality for python 2.7.

Error was :

ERROR: Complete output from command python setup.py egg_info:
    ERROR: Traceback (most recent call last):
      File "<string>", line 1, in <module>
      File "/tmp/pip-install-TzgjyK/slycot/setup.py", line 279, in <module>
        setup_package()
      File "/tmp/pip-install-TzgjyK/slycot/setup.py", line 210, in setup_package
        VERSION, gitrevision = get_version_info(src_path)
      File "/tmp/pip-install-TzgjyK/slycot/setup.py", line 149, in get_version_info
        FULLVERSION = setupcfg['metadata'].get('version', 'Unknown')
    AttributeError: ConfigParser instance has no attribute '__getitem__'
    ----------------------------------------

the .travis.yml file contains a wrong python 3.5 and 3.6 configuration.

[roryyorke]

Looks good, thank you. For the record, to trigger this bug setup.cfg must exist and .git must not. To trigger the bug, I first ran "setup.py sdist", unpacked the source distribution, and ran 'setup.py`.

If possible, please try not to include unrelated white-space changes in future PRs -- it adds a little speed-bump to reviewing.

[jgspiro]

@roryyorke You are correct about what is required to trigger the install issue. Note that this is the case when installing Slycot from PyPI since the sources are released there.