A compromise integration of LVMetaD into the build: I have kept all the

A compromise integration of LVMetaD into the build: I have kept all the
daemon/common code in a single libdaemon.a, which is completely private. This
is currently linked into the lvmetad binary, and will be linked into LVM (the
client part, since static linking only picks up only symbols that are actually
used). I have also added --enable/disable-lvmetad to ./configure; although the
current default is off, I expect this to be flipped to on shortly. There's no
LVM-side support yet, but when there is, even when built, it'll still need to
be enabled by an lvm.conf option.