BUG: Disable ThreadPools by default
BUG: Disable ThreadPools by default

Currently, using thread pools are unstable with MSVC and shared
libraries resulting in random test failing due to threads hanging.

Change-Id: Id8afa5a0ae3f9ff89d4f3f8f49ab940880dd260f

BRAINSia/ITK,richardbeare/ITK,blowekamp/ITK,LucasGandel/ITK,Kitware/ITK,LucasGandel/ITK,vfonov/ITK,spinicist/ITK,thewtex/ITK,malaterre/ITK,spinicist/ITK,stnava/ITK,Kitware/ITK,vfonov/ITK,InsightSoftwareConsortium/ITK,richardbeare/ITK,malaterre/ITK,LucasGandel/ITK,LucasGandel/ITK,hjmjohnson/ITK,richardbeare/ITK,blowekamp/ITK,Kitware/ITK,fbudin69500/ITK,thewtex/ITK,Kitware/ITK,richardbeare/ITK,stnava/ITK,BRAINSia/ITK,Kitware/ITK,richardbeare/ITK,vfonov/ITK,thewtex/ITK,LucasGandel/ITK,spinicist/ITK,fbudin69500/ITK,malaterre/ITK,stnava/ITK,thewtex/ITK,LucasGandel/ITK,blowekamp/ITK,fbudin69500/ITK,LucasGandel/ITK,InsightSoftwareConsortium/ITK,spinicist/ITK,thewtex/ITK,InsightSoftwareConsortium/ITK,blowekamp/ITK,spinicist/ITK,fbudin69500/ITK,richardbeare/ITK,blowekamp/ITK,malaterre/ITK,fbudin69500/ITK,BRAINSia/ITK,BRAINSia/ITK,stnava/ITK,spinicist/ITK,stnava/ITK,thewtex/ITK,richardbeare/ITK,vfonov/ITK,blowekamp/ITK,spinicist/ITK,malaterre/ITK,fbudin69500/ITK,malaterre/ITK,Kitware/ITK,InsightSoftwareConsortium/ITK,hjmjohnson/ITK,BRAINSia/ITK,vfonov/ITK,Kitware/ITK,malaterre/ITK,stnava/ITK,BRAINSia/ITK,hjmjohnson/ITK,fbudin69500/ITK,blowekamp/ITK,vfonov/ITK,malaterre/ITK,spinicist/ITK,hjmjohnson/ITK,vfonov/ITK,hjmjohnson/ITK,hjmjohnson/ITK,stnava/ITK,InsightSoftwareConsortium/ITK,InsightSoftwareConsortium/ITK,vfonov/ITK,vfonov/ITK,fbudin69500/ITK,malaterre/ITK,hjmjohnson/ITK,LucasGandel/ITK,InsightSoftwareConsortium/ITK,spinicist/ITK,stnava/ITK,stnava/ITK,thewtex/ITK,blowekamp/ITK,BRAINSia/ITK