config/configure: find bash via env (as we should)
config/configure: find bash via env (as we should)

Thanks to Greg Troxel <gdt@lexort.com> for reporting the problem.

Signed-off-by: Rob Browning <1dc5917c2adeeba13d1ef33dbb40691a1b67cc65@defaultvalue.org>
Tested-by: Rob Browning <1dc5917c2adeeba13d1ef33dbb40691a1b67cc65@defaultvalue.org>

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