Corrections to misleading comments.

generic/tcl.h

@@ -831,19 +831,20 @@ typedef struct Tcl_Obj {
     union {			/* The internal representation: */
 	long longValue;		/*   - an long integer value. */
 	double doubleValue;	/*   - a double-precision floating value. */
-	void *otherValuePtr;	/*   - another, type-specific value,
-	                       not used internally any more. */
+	void *otherValuePtr;	/*   - another, type-specific value, not used
+				 *     internally any more. */
 	Tcl_WideInt wideValue;	/*   - a long long value. */
 	struct {		/*   - internal rep as two pointers.
-				 *     the main use of which is a bignum's
+				 *     Many uses in Tcl, including a bignum's
 				 *     tightly packed fields, where the alloc,
 				 *     used and signum flags are packed into
-				 *     ptr2 with everything else hung off ptr1. */
+				 *     ptr2 with everything else hung off
+				 *     ptr1. */
 	    void *ptr1;
 	    void *ptr2;
 	} twoPtrValue;
 	struct {		/*   - internal rep as a pointer and a long,
-	                       not used internally any more. */
+				 *     not used internally any more. */
 	    void *ptr;
 	    unsigned long value;
 	} ptrAndLongRep;