Bootman should select boot partitions more intelligently

[tangobravo]

After seeing a few bugs marked "invalid" when people are trying to boot the wrong partition with bootman, it occurred to me a better solution would be to make bootman a bit more intelligent at finding which partitions should be booted.

For example, new versions of windows often have a small boot partition which should be selected, which bootman could try to detect. It would also be nice if we could check if there's already something like GRUB installed (and maybe even read its configuration).

Low priority enhancement, but the fewer people we scare about not being able to boot into their old system again, the better :)

[laplace]

Assigned to nobody, as ATM it is unlikely that I will implement that.

[jonas.kirilla]

The grub idea is mentioned in #3822 (Installer).