[css-inline] add issue to bikeshed hanging and hebrew values for initial-letter-alignment

Author: dauwhe

css-inline/Overview.bs

@@ -496,6 +496,8 @@ Values have the following meanings:
 	as the <a>over</a> and <a>under</a> alignment points, respectively.
 </dl>
 
+Issue: Bikeshed names of hanging and hebrew alignment points. Are there proper typographic terms for these?
+
 <div class="example">
 The vertical writing mode example from <a href="#f2">Figure 2</a> could be coded as: