fix B18002 and B18003 - #rub worn blindfold and wield_tool() feedback

Prevent #rub from wielding an item that is already being worn
(which should narrow things down to the various types of eyewear;
other tools and weapons that go through wield_tool() can't be worn).
Fix up the wield_tool message spacing in the process.

     This moves wield_tool() from apply.c to wield.c.  Some plural
handling for messages is included; it is feasible to try to #rub a
"pair of lenses" or a stack of N candles.

doc/fixes34.1

@@ -367,6 +367,7 @@ when adding an object to inventory, it is possible for it to becomed both
 include rocks as likely candidates for quivering if alternate weapon is a sling
 Asmodeus fails an is_armed() check, so code in m_initweap() to give him wands 
 	of fire and cold never got called; move the code to m_initinv()
+#rub would wield the target tool even when already being worn as eyewear
 
 
 Platform- and/or Interface-Specific Fixes