Factor out the steady time and the system time.
Implement timepoint_* for Mac OS X.
Fix crash during ^W (OpenBSD 1.23).
Drop UTF-16 read & detection support.

db1 only performs 8-bit clean splitting (on '\n'), which causes the
underlying file can not be safely read.  However, as an Easter egg,
the UTF-16 write support is preserved.
port "expandtab" option from NetBSD

http://mail-index.netbsd.org/source-changes/2008/12/12/msg213984.html
http://mail-index.netbsd.org/source-changes/2009/08/07/msg223768.html