Clean-up of blktap and parallax user space code.

Clean-up of blktap and parallax user space code.
Move parallax stuff to its own sub directory and tidy Makefiles a bit.
Signed-off-by: andrew.warfield@cl.cam.ac.uk
Signed-off-by: Nguyen Anh Quynh <aquynh@gmail.com>
--HG--
rename : tools/blktap/README-PARALLAX => tools/blktap/parallax/README
rename : tools/blktap/block-async.c => tools/blktap/parallax/block-async.c
rename : tools/blktap/block-async.h => tools/blktap/parallax/block-async.h
rename : tools/blktap/blockstore.c => tools/blktap/parallax/blockstore.c
rename : tools/blktap/blockstore.h => tools/blktap/parallax/blockstore.h
rename : tools/blktap/blockstored.c => tools/blktap/parallax/blockstored.c
rename : tools/blktap/bstest.c => tools/blktap/parallax/bstest.c
rename : tools/blktap/parallax.c => tools/blktap/parallax/parallax.c
rename : tools/blktap/radix.c => tools/blktap/parallax/radix.c
rename : tools/blktap/radix.h => tools/blktap/parallax/radix.h
rename : tools/blktap/requests-async.c => tools/blktap/parallax/requests-async.c
rename : tools/blktap/requests-async.h => tools/blktap/parallax/requests-async.h
rename : tools/blktap/snaplog.c => tools/blktap/parallax/snaplog.c
rename : tools/blktap/snaplog.h => tools/blktap/parallax/snaplog.h
rename : tools/blktap/vdi.c => tools/blktap/parallax/vdi.c
rename : tools/blktap/vdi.h => tools/blktap/parallax/vdi.h
rename : tools/blktap/vdi_create.c => tools/blktap/parallax/vdi_create.c
rename : tools/blktap/vdi_fill.c => tools/blktap/parallax/vdi_fill.c
rename : tools/blktap/vdi_list.c => tools/blktap/parallax/vdi_list.c
rename : tools/blktap/vdi_snap.c => tools/blktap/parallax/vdi_snap.c
rename : tools/blktap/vdi_snap_delete.c => tools/blktap/parallax/vdi_snap_delete.c
rename : tools/blktap/vdi_snap_list.c => tools/blktap/parallax/vdi_snap_list.c
rename : tools/blktap/vdi_tree.c => tools/blktap/parallax/vdi_tree.c
rename : tools/blktap/vdi_unittest.c => tools/blktap/parallax/vdi_unittest.c
rename : tools/blktap/vdi_validate.c => tools/blktap/parallax/vdi_validate.c