Fix assorted typos.

From https://sourceforge.net/p/swig/patches/332/ and some others too.

Doc/Manual/Allegrocl.html

@@ -1118,7 +1118,7 @@ namespace BAR {
       function that returns an object (or pointer/reference) of C/C++
       type <tt>X</tt>, the wrapping defun (or defmethod) on the Lisp
       side will automatically wrap the pointer returned in an instance
-      of the apropriate class. This makes it much easier to write and
+      of the appropriate class. This makes it much easier to write and
       debug code than if pointers were passed around as a jumble of
       integer values.
     </p>

Doc/Manual/Extending.html

@@ -2975,7 +2975,7 @@ There are a lot of issues to address.
 <div class="code">
 <pre>
 virtual int functionWrapper(Node *n) {
-  /* get useful atributes */
+  /* get useful attributes */
   String   *name   = Getattr(n,"sym:name");
   SwigType *type   = Getattr(n,"type");
   ParmList *parms  = Getattr(n,"parms");