[Groff] lacking characters in groff_char.man

[Bernd Warken]

The following characters can't be shown with groff_char.man:

\[.j]   \e[.j]  dotlessj        u0237   j without a dot
\[vA]   \e[vA]  uni21D5 u21D5   vertical double arrow in both directions
\[-+]   \e[-+]  uni2213 u2213   minus-plus
\[coproduct]    \e[coproduct]   uni2210 u2210   coproduct
\[u2661]        \e[u2661]       uni2661 u2661   white heart suit
\[u2662]        \e[u2662]       uni2662 u2662   white diamond suit

The other characters seem to work.

Bernd Warken