hashsplit.py: create blob objects by hand, not with 'git hash-object'
hashsplit.py: create blob objects by hand, not with 'git hash-object'

Much quicker this way, since we never need to fork anything.

pombredanne/bup,pombredanne/bup,pombredanne/bup,mhoeher/bup,tjanez/bup,mhoeher/bup,jbaber/bup,pombredanne/bup,jbaber/bup,apenwarr/bup,gevaerts/bup,jbaber/bup,gevaerts/bup,pombredanne/bup,pombredanne/bup,mhoeher/bup,tjanez/bup,tjanez/bup,jbaber/bup,ToxicFrog/bup,mhoeher/bup,tjanez/bup,ToxicFrog/bup,gevaerts/bup,apenwarr/bup,ToxicFrog/bup,jbaber/bup,apenwarr/bup,gevaerts/bup,mhoeher/bup,ToxicFrog/bup,apenwarr/bup,mhoeher/bup,tjanez/bup,gevaerts/bup,tjanez/bup,jbaber/bup,ToxicFrog/bup