Convert tabs to spaces in written files

[crokita]

Bug Report

This is less a bug and more a style issue, but there is an inconsistent style of writing files across the project where sometimes tabs are used and sometimes spaces are used. The files should be using one type of indentation.

Expected Behavior

Only spaces should be used as indentation.

Observed Behavior

There is a mix of tabs and spaces across all files.

All versions are affected.