libc: Add swscanf_l() and vwscanf_l().
Add a wscanf_l.3 manual page, modeled after scanf_l.3.
libc: Oops, typo in the Makefile.
w{print,scan}f_l.3: Fix manual page titles.
wscanf_l.3: Fix description.
Use 'static' where appropriate

Patch-from: Eitan Adler <lists@eitanadler.com>
libc: Add atof_l(), atoi_l(), atol_l() and atoll_l().
wscanf_l.3: Adjust wording yet again to match scanf_l.3.