[TYPO3-v4] Install Tool: Combine cleanup modules

[Steffen Gebert]

Hi (Patrick),

thanks for the revamped install tool. It really looks great.

What do you think of merging the two submodules "typo3temp/" and "Clean up  
database" to one module "Cleanup"?
Both have very similar functions and aren't so frequently used, I think.

Thanks in advance
Steffen