Rename prompt-toolkit dependency to prompt_toolkit

.travis.yml

@@ -9,7 +9,7 @@ install:
   - "python -m pip install pip --upgrade"
   - "pip install ."
   - "pip install .[ical]"
-  - "pip install .[prompt-toolkit]"
+  - "pip install .[prompt_toolkit]"
   - "pip install .[test]"
   - "pip install pylint"
   - "pip install codecov"

setup.py

@@ -35,7 +35,7 @@ setup(
         ':sys_platform=="win32"': ['colorama>=0.2.5'],
         ':python_version=="3.2"': ['backports.shutil_get_terminal_size>=1.0.0'],
         'ical': ['icalendar'],
-        'prompt-toolkit': ['prompt-toolkit >= 0.53'],
+        'prompt_toolkit': ['prompt_toolkit >= 0.53'],
         'test': ['coverage', 'freezegun', 'green', ],
         'test:python_version=="3.2"': ['mock'],
     },