added prompt-toolkit to setup requirements

requirements/base.txt

@@ -1,4 +1,5 @@
 Click==7.0
+prompt-toolkit>=3.0.2
 pyaml==19.4.1
 PyYAML==5.1.2
 SQLAlchemy==1.3.11

setup.py

@@ -8,6 +8,7 @@ setup(
     install_requires=[
         "setuptools",
         "click",
+        "prompt-toolkit",
         "pyaml",
         "sqlalchemy",
         "tabulate",