added configs for Calculate(gentoo-based),Gentoo

[valentin-mu]

[ZLima12]

Thanks for providing these configs. I tried to use the Gentoo config, but it seems as though the kernel and initrd has been moved from /isolinux/ to /boot/. I'm not sure about Calculate, but if it's Gentoo based, it might also be affected. For now, I'll go ahead and create a PR with the Gentoo fix at @valentin-mu 's fork.

[ZLima12]

Of course, if @thias would like to pull from my branch, he should be able to do so. (assuming @valentin-mu allowed permission)

[thias]

Better late than never! I've added Calculate Linux in 14741d9.