stabilize the last few doc changes

- display Luis's name with an accent
- @sc the warranty
- remove @code from section headings and @seealso
- reword no-long-long note again
- hey, define-foreign-library supports multiple libraries
- clarify what *darwin-framework-directories* is actually used for
- reorganize *foreign-library-directories* description
- in gendocs.sh, fix libtool links as well