Well, hopefully the question is self-explanatory.
It's so easy to select a block of code and tab out, but how about the reverse?
Currently, I just search & replace for whitespace at the beginning of the line. Anything faster?
In Visual Studio and most other half decent IDEs you can simply do SHIFT+TAB. It does the opposite of just TAB.
I would think and hope that the IDEs you mention support this as well.