mind flayers growing up into master mind flayers, etc.

While one could argue that giant rats aren't just grown up forms of sewer
rats, we already have bat/giant bat in there.

doc/fixes34.1

@@ -200,6 +200,8 @@ prevent "the mimic looks better" on an unrecognized mimic hit with
 	healing spell
 after forcefighting a concealed lurker, the lurker wouldn't fight back
 when polymorphed into a hider, cease hiding during level changes
+let mind flayer grow up into master mind flayer; also giant/sewer rat and
+	cave/large spider
 
 
 Platform- and/or Interface-Specific Fixes

src/mondata.c

@@ -527,6 +527,10 @@ static const short grownups[][2] = {
 	{PM_KOBOLD, PM_LARGE_KOBOLD}, {PM_LARGE_KOBOLD, PM_KOBOLD_LORD},
 	{PM_GNOME, PM_GNOME_LORD}, {PM_GNOME_LORD, PM_GNOME_KING},
 	{PM_DWARF, PM_DWARF_LORD}, {PM_DWARF_LORD, PM_DWARF_KING},
+	{PM_MIND_FLAYER, PM_MASTER_MIND_FLAYER},
+	{PM_ORC, PM_ORC_CAPTAIN},
+	{PM_SEWER_RAT, PM_GIANT_RAT},
+	{PM_CAVE_SPIDER, PM_GIANT_SPIDER},
 	{PM_OGRE, PM_OGRE_LORD}, {PM_OGRE_LORD, PM_OGRE_KING},
 	{PM_ELF, PM_ELF_LORD}, {PM_WOODLAND_ELF, PM_ELF_LORD},
 	{PM_GREEN_ELF, PM_ELF_LORD}, {PM_GREY_ELF, PM_ELF_LORD},