Log Message:
Update to 1.9.8. Use github versioned tarball, set LICENSE,
mark as build-only dependency in buildlink3.mk, remove unnecessary
USE_LANGUAGES, install documentation, install all headers.

Version 1.9.8 (2013-03-10)
    HASH_REPLACE now in uthash (thanks, Nick Vatamaniuc!)
    fixed clang warnings (thanks wynnw!)
    fixed utarray_insert when inserting past array end (thanks Rob Willett!)
    you can now find uthash on GitHub
    there’s a uthash Google Group
    uthash has been downloaded 29,000+ times since 2006 on SourceForge