This patch is an incomplete and untested patch against lftp 3-4-7. The initial
code was written before trying to build the unmodified package. When trying to
build for testing, it turns out it won't configure or build correctly. After
an hour or so of trying to fix it, I bailed.

TODO
----
- get original package to build
- build with patch
- add needed code to parse/set 'dns:strict-dnssec' config option
- check if presentation of errors to user works
- add configure testing for libval and set LOCAL_DNSSEC_VALIDATION