glyphs: rotate-5 in glyph_hash eliminates true collisions

The previous rotate-1-xor put consecutive characters' bits in
adjacent positions, so short similar names like fox/bat or
jaguar/lichen collided -- 164 colliding buckets across the 9577
named glyphs.  Rotate-5 spreads each character across a 5-bit
window: zero true collisions, one m68k ROL.L, no multiplication.

The 16 remaining same-hash buckets are name duplicates from a
separate compose_glyph_name bug, addressed by its own fix.

src/glyphs.c

@@ -618,7 +618,7 @@ glyph_hash(const char *id)
         if ('A' <= ch && ch <= 'Z') {
             ch += 'a' - 'A';
         }
-        hash = (hash << 1) | (hash >> 31);
+        hash = (hash << 5) | (hash >> 27);
         hash ^= ch;
     }
     return hash;