README: mention the need of pkgconfig at build time
PV: add size parameter to pv_create() constructor (upstream API change)

There needs to be some more fix as upstream has done quite some changes to the
API and the commit that introduced that lvm_pv_create new function.
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commit 6d6ccded3590b46f214561db38e1ce084b643c13
Author: Tony Asleson <tasleson@redhat.com>
Date:   Wed Apr 3 17:53:21 2013 -0400

    lib2app: Added PV create. V2

    V2: Correct call to lock_vol

    Signed-off-by: Tony Asleson <tasleson@redhat.com>
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src: move PV, VG, LV typedefs to LVM nobj file
LVM/VG: add vg_open method to LVM handle object and removed it as constructor for VG object
VG: add list_lvs method
LVM: add vg_create() method