Remove requirements files we shouldn't be using anymore

requirements/dev.txt

@@ -1,12 +0,0 @@
--r base.txt
-
-mock>=2.0.0
-SaltPyLint>=v2017.3.6
-testinfra>=1.7.0,!=1.17.0
-
-# httpretty Needs to be here for now even though it's a dependency of boto.
-# A pip install on a fresh system will decide to target httpretty 0.8.10 to
-# satisfy other requirements, and httpretty 0.8.10 has bugs in setup.py that
-# prevent it from being successfully installed (at least on Python 3.4).
-httpretty; python_version >= '3.4'
-pylint==1.6.5

requirements/dev_python27.txt

@@ -1,2 +0,0 @@
-# This is a legacy file, use dev.txt
--r dev.txt

requirements/dev_python34.txt

@@ -1,2 +0,0 @@
-# This is a legacy file, use dev.txt
--r dev.txt

requirements/opt.txt

@@ -1,9 +0,0 @@
-mysql-python
-timelib
-yappi>=0.8.2
---allow-unverified python-novaclient>2.17.0
---allow-unverified python-neutronclient>2.3.6
-python-gnupg
-cherrypy>=3.2.2,<18.0.0; python_version < '3.5'
-cherrypy>=3.2.2; python_version >= '3.5'
-libnacl

requirements/tests.txt

@@ -1,41 +0,0 @@
--r zeromq.txt
--r dev.txt
--r pytest.txt
-apache-libcloud>=1.0.0
-boto>=2.32.1
-boto3>=1.2.1
-moto>=0.3.6
-docker; sys.platform != 'win32'
-docker==2.7.0; sys.platform == 'win32'
-virtualenv
-setuptools>=30
-six>=1.10.0
-timelib
-coverage
-keyring==5.7.1
-python-gnupg
-python-etcd==0.4.2
-GitPython
-supervisor; python_version < '3'
-kubernetes<4.0
-psutil
-pyvmomi
-setproctitle
-cherrypy>=3.2.2,<18.0.0; python_version < '3.5' and sys.platform != 'win32' and sys.platform != 'darwin'
-cherrypy>=3.2.2; python_version >= '3.5' and sys.platform != 'win32' and sys.platform != 'darwin'
-pyinotify; sys.platform != 'win32' and sys.platform != 'darwin'
-PyMySQL; sys.platform != 'win32' and sys.platform != 'darwin'
-jsonschema
-strict_rfc3339
-rfc3987
-pyOpenSSL
-ioflo
-dnspython
-SaltTesting==2017.6.1
-junos-eznc
-jxmlease
-croniter
-kazoo
-ansible; sys.platform != 'win32' and sys.platform != 'darwin' and python_version >= '3.5'
-ansible; sys.platform != 'win32' and sys.platform != 'darwin' and python_version == '2.7'
-pylxd>=2.2.5; sys.platform != 'win32' and sys.platform != 'darwin'