Log message:
Update ptexenc to 1.2.0.

Changes:
        * ptexenc.c, ptexenc/ptexenc.h: Export toUCS().
        * ptexenc/unicode.h: Export UCStoUTF8().
        * ptexenc.c: Change version string "ptetex" => \ 
"ptexenc".
        * Makefile.am: Install ptexenc/unicode.h.

Log message:
Import ptexenc-1.1.1 as print/ptexenc.

ptexenc is a useful library for Japanese pTeX (which stands for
publishing TeX, and is an extension of TeX by ASCII Co.) and its
surrounding tools.  ptexenc provides a better way of handling
character encodings.