Problems with boot installation

[rustamzh]

Hi, I decided to try the distr on my actual machine planning to dual boot it along with my other OSes. Got a very unexpected surprise by the installer overriding my boot partition, deleting Grub and windows bootloaders. I think it is probably necessary for immutability but the warning would be deeply appreciated somewhere in the docs, announcement, installer, etc. Booting live the second time I realized that installer does not even offer to choose a boot partition, which is a big obstacle for dual boot adoption. Now I created another boot partition, recovering Windows and grub, which I plan to use to chain boot systemd-boot.

Suggestions:

• Please add warnings about boot partition overwrite to docs, announcements, installers, etc.
• Please add an option to specify the boot partition.