title: the yowsup library does not work when I try to register
body: <p>I installed the next packages in my raspberry with pip3:
  -python-axolotl
  -protobuf
  -six
  -argparse
  -readline
  -pillow
  -tqdm
  -requests
  -pycrypto
  -blinker</p>
  
  <p>Next I installed yowsup with</p>
  
  <p>pip3 install yowsup</p>
  
  <p>So, I download a repository, <a href="https://github.com/danielcardeenas/whatsapp-framework" rel="nofollow noreferrer">https://github.com/danielcardeenas/whatsapp-framework</a>, (today is 2019-May-17), I live in Colombian, so I intent send the registration with:
  yowsup-cli registration --requestcode sms --phone 57317509xxx --cc 57 -E android</p>
  
  <p>I installed the next packages in my raspberry with pip3:
  -python-axolotl
  -protobuf
  -six
  -argparse
  -readline
  -pillow
  -tqdm
  -requests
  -yowsup
  -pycrypto
  -blinker</p>
  
  <p>next, I download a repository, <a href="https://github.com/danielcardeenas/whatsapp-framework" rel="nofollow noreferrer">https://github.com/danielcardeenas/whatsapp-framework</a>, (today is 2019-May-17), I live in Colombian, so I intent send the registration with:
  yowsup-cli registration --requestcode sms --phone 57317509xxx --cc 57 -E android</p>
  
  <p>but the console print a error:</p>
  
  <p>Traceback (most recent call last):
  File "/usr/local/bin/yowsup-cli", line 4, in 
  import('pkg_resources').run_script('yowsup2==2.5.2', 'yowsup-cli')
  File "/usr/lib/python3/dist-packages/pkg_resources/init.py", line 739, in run_script
  self.require(requires)[0].run_script(script_name, ns)
  File "/usr/lib/python3/dist-packages/pkg_resources/init.py", line 1494, in run_script
  exec(code, namespace, namespace)
  File "/usr/local/lib/python3.5/dist-packages/yowsup2-2.5.2-py3.5.egg/EGG-INFO/scripts/yowsup-cli", line 368, in 
  if not parser.process():
  File "/usr/local/lib/python3.5/dist-packages/yowsup2-2.5.2-py3.5.egg/EGG-INFO/scripts/yowsup-cli", line 189, in process
  self.handleRequestCode(self.args["requestcode"], config)
  File "/usr/local/lib/python3.5/dist-packages/yowsup2-2.5.2-py3.5.egg/EGG-INFO/scripts/yowsup-cli", line 198, in handleRequestCode
  from yowsup.registration import WACodeRequest
  File "/usr/local/lib/python3.5/dist-packages/yowsup/registration/init.py", line 1, in 
  from .coderequest import WACodeRequest
  File "/usr/local/lib/python3.5/dist-packages/yowsup/registration/coderequest.py", line 1, in 
  from yowsup.common.http.warequest import WARequest
  File "/usr/local/lib/python3.5/dist-packages/yowsup/common/http/init.py", line 2, in 
  from .warequest import WARequest
  File "/usr/local/lib/python3.5/dist-packages/yowsup/common/http/warequest.py", line 8, in 
  from yowsup.common.tools import WATools
  File "/usr/local/lib/python3.5/dist-packages/yowsup/common/tools.py", line 10, in 
  from consonance.structs.keypair import KeyPair
  File "/usr/local/lib/python3.5/dist-packages/consonance/structs/keypair.py", line 4, in 
  from dissononce.dh.x25519.x25519 import X25519DH
  File "/usr/local/lib/python3.5/dist-packages/dissononce/dh/x25519/x25519.py", line 1, in 
  from cryptography.hazmat.primitives.asymmetric import x25519
  ImportError: cannot import name 'x25519'</p>