Jan Synacek authored Feb 11, 2015 and Quanah Gibson-Mount committed Feb 11, 2015

The old cpp version generated:
__db_version 5

The new output:
__db_version
            5

Running cpp with -P (inhibit linemarkers generation) fixes this when using gcc 5.
Behavior with older versions of gcc is not changed.

Drop support for BDB 6.0.20 and later, incompatible license

Updated BerkeleyDB version tests

reduce library link tries.

not yet used

Do not use test -a/-o.  Use shell features like &&, || or case...esac.
Use grep instead of egrep (but not the not-yet-portable Posix variant grep -E).
Based on a patch from Paul Eggert.

the passed in help string. (Append the valid args to the help string...)