ENH: Optionally label KWSys targets and tests
ENH: Optionally label KWSys targets and tests

This provides an API for parent projects to use to specify values to be
set in the LABELS properties of KWSys libraries, executables, and tests.

atsnyder/ITK,msmolens/ITK,fedral/ITK,daviddoria/itkHoughTransform,PlutoniumHeart/ITK,jmerkow/ITK,richardbeare/ITK,blowekamp/ITK,fuentesdt/InsightToolkit-dev,hendradarwin/ITK,hjmjohnson/ITK,LucasGandel/ITK,hjmjohnson/ITK,hjmjohnson/ITK,itkvideo/ITK,fbudin69500/ITK,LucasGandel/ITK,heimdali/ITK,thewtex/ITK,biotrump/ITK,ajjl/ITK,vfonov/ITK,atsnyder/ITK,rhgong/itk-with-dom,itkvideo/ITK,GEHC-Surgery/ITK,GEHC-Surgery/ITK,wkjeong/ITK,thewtex/ITK,paulnovo/ITK,LucHermitte/ITK,zachary-williamson/ITK,spinicist/ITK,jcfr/ITK,biotrump/ITK,malaterre/ITK,stnava/ITK,spinicist/ITK,jmerkow/ITK,InsightSoftwareConsortium/ITK,richardbeare/ITK,jcfr/ITK,PlutoniumHeart/ITK,fbudin69500/ITK,eile/ITK,LucasGandel/ITK,wkjeong/ITK,Kitware/ITK,BRAINSia/ITK,biotrump/ITK,InsightSoftwareConsortium/ITK,hjmjohnson/ITK,CapeDrew/DITK,fbudin69500/ITK,msmolens/ITK,hinerm/ITK,rhgong/itk-with-dom,spinicist/ITK,BlueBrain/ITK,biotrump/ITK,jcfr/ITK,eile/ITK,thewtex/ITK,CapeDrew/DCMTK-ITK,itkvideo/ITK,atsnyder/ITK,itkvideo/ITK,InsightSoftwareConsortium/ITK,BRAINSia/ITK,hjmjohnson/ITK,InsightSoftwareConsortium/ITK,eile/ITK,stnava/ITK,stnava/ITK,fuentesdt/InsightToolkit-dev,Kitware/ITK,cpatrick/ITK-RemoteIO,BlueBrain/ITK,richardbeare/ITK,vfonov/ITK,ajjl/ITK,stnava/ITK,CapeDrew/DCMTK-ITK,fbudin69500/ITK,wkjeong/ITK,heimdali/ITK,hendradarwin/ITK,itkvideo/ITK,cpatrick/ITK-RemoteIO,hendradarwin/ITK,vfonov/ITK,thewtex/ITK,jcfr/ITK,hendradarwin/ITK,Kitware/ITK,blowekamp/ITK,fuentesdt/InsightToolkit-dev,atsnyder/ITK,rhgong/itk-with-dom,biotrump/ITK,msmolens/ITK,fedral/ITK,biotrump/ITK,fuentesdt/InsightToolkit-dev,BRAINSia/ITK,zachary-williamson/ITK,paulnovo/ITK,blowekamp/ITK,vfonov/ITK,rhgong/itk-with-dom,hendradarwin/ITK,jmerkow/ITK,malaterre/ITK,PlutoniumHeart/ITK,heimdali/ITK,msmolens/ITK,jmerkow/ITK,cpatrick/ITK-RemoteIO,wkjeong/ITK,Kitware/ITK,fedral/ITK,eile/ITK,cpatrick/ITK-RemoteIO,fedral/ITK,blowekamp/ITK,zachary-williamson/ITK,paulnovo/ITK,CapeDrew/DCMTK-ITK,zachary-williamson/ITK,jmerkow/ITK,ajjl/ITK,hinerm/ITK,hinerm/ITK,fbudin69500/ITK,malaterre/ITK,heimdali/ITK,jmerkow/ITK,LucasGandel/ITK,paulnovo/ITK,hendradarwin/ITK,eile/ITK,ajjl/ITK,fbudin69500/ITK,LucHermitte/ITK,vfonov/ITK,daviddoria/itkHoughTransform,zachary-williamson/ITK,paulnovo/ITK,thewtex/ITK,fedral/ITK,hjmjohnson/ITK,GEHC-Surgery/ITK,CapeDrew/DCMTK-ITK,fedral/ITK,LucHermitte/ITK,BlueBrain/ITK,BlueBrain/ITK,LucasGandel/ITK,atsnyder/ITK,daviddoria/itkHoughTransform,thewtex/ITK,cpatrick/ITK-RemoteIO,spinicist/ITK,wkjeong/ITK,BlueBrain/ITK,jcfr/ITK,BlueBrain/ITK,InsightSoftwareConsortium/ITK,CapeDrew/DITK,heimdali/ITK,msmolens/ITK,fedral/ITK,fedral/ITK,hendradarwin/ITK,stnava/ITK,jcfr/ITK,blowekamp/ITK,eile/ITK,PlutoniumHeart/ITK,fuentesdt/InsightToolkit-dev,CapeDrew/DCMTK-ITK,hinerm/ITK,LucasGandel/ITK,malaterre/ITK,hinerm/ITK,BlueBrain/ITK,LucHermitte/ITK,LucasGandel/ITK,ajjl/ITK,daviddoria/itkHoughTransform,stnava/ITK,hinerm/ITK,daviddoria/itkHoughTransform,spinicist/ITK,blowekamp/ITK,rhgong/itk-with-dom,BRAINSia/ITK,CapeDrew/DITK,itkvideo/ITK,wkjeong/ITK,rhgong/itk-with-dom,CapeDrew/DCMTK-ITK,msmolens/ITK,CapeDrew/DCMTK-ITK,hinerm/ITK,spinicist/ITK,zachary-williamson/ITK,CapeDrew/DITK,atsnyder/ITK,richardbeare/ITK,GEHC-Surgery/ITK,richardbeare/ITK,spinicist/ITK,BRAINSia/ITK,PlutoniumHeart/ITK,malaterre/ITK,msmolens/ITK,heimdali/ITK,paulnovo/ITK,hendradarwin/ITK,biotrump/ITK,GEHC-Surgery/ITK,LucHermitte/ITK,fbudin69500/ITK,hjmjohnson/ITK,rhgong/itk-with-dom,PlutoniumHeart/ITK,richardbeare/ITK,LucasGandel/ITK,vfonov/ITK,cpatrick/ITK-RemoteIO,CapeDrew/DCMTK-ITK,ajjl/ITK,fuentesdt/InsightToolkit-dev,eile/ITK,jcfr/ITK,paulnovo/ITK,stnava/ITK,BRAINSia/ITK,itkvideo/ITK,zachary-williamson/ITK,CapeDrew/DITK,CapeDrew/DITK,PlutoniumHeart/ITK,atsnyder/ITK,vfonov/ITK,zachary-williamson/ITK,daviddoria/itkHoughTransform,malaterre/ITK,stnava/ITK,wkjeong/ITK,spinicist/ITK,GEHC-Surgery/ITK,GEHC-Surgery/ITK,atsnyder/ITK,daviddoria/itkHoughTransform,vfonov/ITK,CapeDrew/DCMTK-ITK,malaterre/ITK,LucHermitte/ITK,thewtex/ITK,rhgong/itk-with-dom,jcfr/ITK,heimdali/ITK,stnava/ITK,eile/ITK,biotrump/ITK,fuentesdt/InsightToolkit-dev,daviddoria/itkHoughTransform,heimdali/ITK,fuentesdt/InsightToolkit-dev,malaterre/ITK,cpatrick/ITK-RemoteIO,blowekamp/ITK,BlueBrain/ITK,fbudin69500/ITK,CapeDrew/DITK,spinicist/ITK,InsightSoftwareConsortium/ITK,atsnyder/ITK,paulnovo/ITK,hinerm/ITK,hinerm/ITK,BRAINSia/ITK,ajjl/ITK,LucHermitte/ITK,msmolens/ITK,CapeDrew/DITK,daviddoria/itkHoughTransform,LucHermitte/ITK,CapeDrew/DITK,ajjl/ITK,itkvideo/ITK,Kitware/ITK,jmerkow/ITK,GEHC-Surgery/ITK,jmerkow/ITK,zachary-williamson/ITK,PlutoniumHeart/ITK,fuentesdt/InsightToolkit-dev,Kitware/ITK,InsightSoftwareConsortium/ITK,vfonov/ITK,eile/ITK,itkvideo/ITK,Kitware/ITK,wkjeong/ITK,richardbeare/ITK,cpatrick/ITK-RemoteIO,blowekamp/ITK,malaterre/ITK