Allow us to close portions of the debugger

- [x] I'm using the latest version of react-native-debugger
- [x] I have read [README.md](https://github.com/jhen0409/react-native-debugger/blob/master/README.md)

React Native version: [0.40.0]
Platform: [Android]
Is real device of platform: [No]? (Phrasing of this is odd - I'm using an emulator atm)
Operating System: [Windows]

-----
There are times when I'm doing UI work and there are times when all I want is a console. Please allow us the option to close portions of the debugger. It's not very space efficient to hit the `Toggle React-Tools` and it turns off but the frame is still there and cannot be shrunk to a smaller size.


As you can see from the above screenshot it kind of takes up unnecessary space when tiling windows in specific ways

The issue points to the debugger window layout and the Toggle React-Tools control; start by locating those UI entry points. Done means debugger sections can be closed or reduced so the remaining console or tools use space efficiently, including the Windows layout shown in the report.

Scritto dal modello di indicizzazione a partire dal testo della issue.