Bug#1021750: general: the nodelalloc mount option should be used by default for ext4 in /etc/fstab

[nick black]

i'm pretty sure that the corruption issues leading to the
nodelalloc option were considered largely remedied by the
"auto_da_alloc" capability introduced (and enabled by default)
in 2.6.30? how would nodelalloc equal the performance of
delalloc? nodelalloc was all about reliability for programs that
weren't conforming to certain POSIX semantics, as i recall.