Remove dhcpdb.bind file if changed dhcpdb.pool file.
If dhcpdb.pool file is changed and dhcpdb.bind file is
not matched to new pool file, dhcp server(dhcps) can not
run with some errors like this.
* dhcps in free(): warning: modified (chunk-) pointer.
* dhcps[25591]: hash_ins() with client identifier failed in read_bind_db()
I fixed start-up script to remove dhcpdb.bind file
when dhcpdb.pool file is newer than dhcpdb.bind.
Install intro.dhcp.jis file into ${PREFIX}/share/dhcp dirctory.
PR: 3717
Submitted-by: sanpei@yy.cs.keio.ac.jp