[odb-users] build2 interactive confirm : Y vs y

[Boris Kolpackov]

MM <finjulhich at gmail.com> writes:

> continue? [Y/n] Y
> continue? [Y/n] y
> 
> 
> If one enters uppercase Y, if fails to start.   lowercase y is accepted.

By convention a capital Y or N in a prompt indicates the default answer,
that is, the answer that will be assumed if one just presses Enter. But
you are the second person who insist on typing an explicit, capitalized
answer, so we've fixed the prompt to accept both cases.