VM creation: additional clean-up

Given that we often make a "pre-release" VM and then update it, I found it a bit dangerous as I initially forgot to delete some files. I therefore suggest to add
```
cd ~
rm -f .*history .sudo_as_admin_successful .gitconfig  .lesshst 
```
and maybe some more to https://github.com/SyneRBI/SIRF-SuperBuild/blob/master/VirtualBox/scripts/clean_before_VM_export.sh

@paskino what do you think?