Support for signals is not available on Windows

[daeeros]

Expected Behavior

App need to start.

Actual Behavior

App shooting down with NotImplementedError in add_signal_handler (file > kutana.py > line(203) > (add_signal_handler)

Possible Solution

Make the correct exception handler in the event loop.

Steps to Reproduce (for bugs)

1. Install all requirements
2. Try to run runer.py
3. We geting the NotImplementedError in add_signal_handler (file > kutana.py > line(203) > (add_signal_handler) will Windows no't support signals.

Context

Your Environment

• Python vesion: 3.6
• Kutana version: 4.1.3
• Platform: Windows 10 x64 (1809)
• Country: Turkey

[michaelkryukov]

Feel free to open, if any issues remains