do_unpack: shift some responsibility around, clean things up
do_unpack: shift some responsibility around, clean things up

- Move the unpacking message printing into do_unpack
- Move the destination directory determination into do_unpack
- Use subprocess's ability to pass in PATH and cwd rather than mangling the cmd
- Use shutil.copy2/copytree for ordinary file "unpack"
- Use the existing urldata from bb.fetch.init rather than re-decodeurl'ing the urls
- Only display the unpack destdir to the user when debugging is enabled, as we
  all know they unpack into WORKDIR

Signed-off-by: Chris Larson <4c8c411260e601995081b113a5ef94a26eff2b25@mentor.com>

Martix/Eonos,nx111/openembeded_openpli2.1_nx111,sledz/oe,xifengchuo/openembedded,nx111/openembeded_openpli2.1_nx111,BlackPole/bp-openembedded,sentient-energy/emsw-oe-mirror,rascalmicro/openembedded-rascal,SIFTeam/openembedded,sentient-energy/emsw-oe-mirror,JamesAng/goe,rascalmicro/openembedded-rascal,mrchapp/arago-oe-dev,BlackPole/bp-openembedded,dellysunnymtech/sakoman-oe,hulifox008/openembedded,dellysunnymtech/sakoman-oe,openembedded/openembedded,dellysunnymtech/sakoman-oe,giobauermeister/openembedded,sutajiokousagi/openembedded,hulifox008/openembedded,giobauermeister/openembedded,bticino/openembedded,bticino/openembedded,BlackPole/bp-openembedded,buglabs/oe-buglabs,openpli-arm/openembedded,thebohemian/openembedded,buglabs/oe-buglabs,sledz/oe,anguslees/openembedded-android,anguslees/openembedded-android,giobauermeister/openembedded,JamesAng/oe,yyli/overo-oe,hulifox008/openembedded,crystalfontz/openembedded,Martix/Eonos,dellysunnymtech/sakoman-oe,openembedded/openembedded,dellysunnymtech/sakoman-oe,JamesAng/oe,buglabs/oe-buglabs,libo/openembedded,openembedded/openembedded,Martix/Eonos,xifengchuo/openembedded,sutajiokousagi/openembedded,giobauermeister/openembedded,dave-billin/overo-ui-moos-auv,John-NY/overo-oe,John-NY/overo-oe,trini/openembedded,bticino/openembedded,openpli-arm/openembedded,sledz/oe,SIFTeam/openembedded,buglabs/oe-buglabs,anguslees/openembedded-android,SIFTeam/openembedded,crystalfontz/openembedded,mrchapp/arago-oe-dev,openembedded/openembedded,John-NY/overo-oe,scottellis/overo-oe,SIFTeam/openembedded,crystalfontz/openembedded,anguslees/openembedded-android,rascalmicro/openembedded-rascal,John-NY/overo-oe,scottellis/overo-oe,buglabs/oe-buglabs,JamesAng/goe,openpli-arm/openembedded,hulifox008/openembedded,sledz/oe,mrchapp/arago-oe-dev,sledz/oe,yyli/overo-oe,sampov2/audio-openembedded,nx111/openembeded_openpli2.1_nx111,libo/openembedded,dave-billin/overo-ui-moos-auv,bticino/openembedded,thebohemian/openembedded,thebohemian/openembedded,dave-billin/overo-ui-moos-auv,giobauermeister/openembedded,sampov2/audio-openembedded,sledz/oe,xifengchuo/openembedded,rascalmicro/openembedded-rascal,JamesAng/oe,nx111/openembeded_openpli2.1_nx111,dave-billin/overo-ui-moos-auv,openpli-arm/openembedded,giobauermeister/openembedded,dave-billin/overo-ui-moos-auv,xifengchuo/openembedded,trini/openembedded,crystalfontz/openembedded,xifengchuo/openembedded,trini/openembedded,John-NY/overo-oe,BlackPole/bp-openembedded,buglabs/oe-buglabs,scottellis/overo-oe,buglabs/oe-buglabs,openembedded/openembedded,bticino/openembedded,Martix/Eonos,sledz/oe,openembedded/openembedded,mrchapp/arago-oe-dev,sutajiokousagi/openembedded,openpli-arm/openembedded,sutajiokousagi/openembedded,thebohemian/openembedded,openembedded/openembedded,thebohemian/openembedded,JamesAng/goe,hulifox008/openembedded,BlackPole/bp-openembedded,xifengchuo/openembedded,crystalfontz/openembedded,yyli/overo-oe,JamesAng/goe,rascalmicro/openembedded-rascal,yyli/overo-oe,mrchapp/arago-oe-dev,Martix/Eonos,SIFTeam/openembedded,xifengchuo/openembedded,libo/openembedded,dave-billin/overo-ui-moos-auv,JamesAng/oe,libo/openembedded,openpli-arm/openembedded,openembedded/openembedded,libo/openembedded,buglabs/oe-buglabs,xifengchuo/openembedded,SIFTeam/openembedded,sentient-energy/emsw-oe-mirror,crystalfontz/openembedded,rascalmicro/openembedded-rascal,trini/openembedded,Martix/Eonos,sampov2/audio-openembedded,nx111/openembeded_openpli2.1_nx111,dave-billin/overo-ui-moos-auv,openpli-arm/openembedded,scottellis/overo-oe,sutajiokousagi/openembedded,scottellis/overo-oe,scottellis/overo-oe,yyli/overo-oe,xifengchuo/openembedded,rascalmicro/openembedded-rascal,sutajiokousagi/openembedded,scottellis/overo-oe,bticino/openembedded,sentient-energy/emsw-oe-mirror,sampov2/audio-openembedded,thebohemian/openembedded,trini/openembedded,openembedded/openembedded,libo/openembedded,sampov2/audio-openembedded,yyli/overo-oe,sutajiokousagi/openembedded,giobauermeister/openembedded,JamesAng/goe,BlackPole/bp-openembedded,sentient-energy/emsw-oe-mirror,anguslees/openembedded-android,dellysunnymtech/sakoman-oe,trini/openembedded,JamesAng/goe,yyli/overo-oe,JamesAng/oe,hulifox008/openembedded,nx111/openembeded_openpli2.1_nx111,nx111/openembeded_openpli2.1_nx111,sampov2/audio-openembedded,JamesAng/goe,giobauermeister/openembedded,mrchapp/arago-oe-dev,JamesAng/oe,trini/openembedded,dellysunnymtech/sakoman-oe,openembedded/openembedded,rascalmicro/openembedded-rascal,sampov2/audio-openembedded,John-NY/overo-oe,Martix/Eonos,sentient-energy/emsw-oe-mirror,mrchapp/arago-oe-dev,dellysunnymtech/sakoman-oe,libo/openembedded,SIFTeam/openembedded,dellysunnymtech/sakoman-oe,hulifox008/openembedded,sentient-energy/emsw-oe-mirror,yyli/overo-oe,giobauermeister/openembedded,crystalfontz/openembedded,JamesAng/oe,anguslees/openembedded-android,openembedded/openembedded,nx111/openembeded_openpli2.1_nx111,BlackPole/bp-openembedded,anguslees/openembedded-android,thebohemian/openembedded,John-NY/overo-oe,bticino/openembedded