Hi
This patch adds support for following:
1) Allow to use either use Tab/Spaces in editor.
2) Allow to specify Tab Size.
This settings are configurable in Preferences and will be applied to all code mirror instances in pgAdmin4.
Also, while setting "Help string" for SwitchControl in preferences. Help string is not aligned with Switch. I moved the help string and checkbox in same div to fix.
Please review and let me know for comments.
Thanks,
Surinder Kumar