[Box Backup] BSD-isms

[Joe Krahn]

A comment on LinuxWorkaround.cpp, LFS support, and others. Most of these 
Linux workarounds are really POSIX work-arounds. BSD has several useful 
features, like statfs.f_mntonname and dirent.d_type, which are not part 
of POSIX. Linux generally follows strict POSIX rules, even thought it 
includes a number of BSD variants for things not part of POSIX.

The result is that the Linux code will be a good fit to other non-BSD 
Unices.

Not that I'm completely defending the Linux OS: if it were up to me, I 
would add more BSD features, with an option to enable non-POSIX warnings.

Joe Krahn