Add Transliterations for Unicode Misc. Mathematical Symbols-A/B [BZ #23132]

This commit adds previously missing transliterations for several code points
in the Unicode blocks "Miscellaneous Mathematical Symbols-A/B" -
transliterated to their approximate ASCII representations.  It also adds a
corresponding iconv transliteration test.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
(cherry picked from commit 513aaa0d)