Remove fabfile.

I'm going to replace it with GitLab CI.

fabfile.py

-from __future__ import (absolute_import, division, print_function,
-                        unicode_literals)
-from fabric.api import (local, task, sudo, env, settings)
-
-env.use_ssh_config = True
-
-
-@task
-def build():
-    '''Build wheel.'''
-    local('''python setup.py sdist bdist_wheel''')
-
-
-@task
-def clean():
-    '''Clean.'''
-    local('''rm -rf *.pyc *.egg-info build dist''')
-
-
-@task
-def upload():
-    build()
-    local('''twine upload -s dist/*''')