en: simplify and fix words starting with 's'.

dictsource/en_rules

         s (s 
         s (sh      s
 
-     _) s (cY      s
-     _) s (cL01Y   s
+     _) s          s
      _) sch        S
      _) sh (Y      S
      _) sh (L01Y   S
-     _) s (kY      s
-     _) s (kL01Y   s
-     _) s (lY      s
      _) s (mY      s
-     _) s (nY      s
-     _) s (pY      s
-     _) s (phY     s
-     _) s (pL01Y   s
-     _) s (qu      s
-     _) s (ri      s
-     _) s (tY      s
-     _) s (trY     s
-     _) s (va      s
-     _) s (ve      s
-     _) s (wY      s
-     _) sz (@@     Sz
+     _) sz (@      S
+     _) szcz (@    S
 
      A) s (al      z
         sche (m    ski: