Bugfix: Correct English grammar regarding "'s"

src/util.cpp

@@ -354,7 +354,7 @@ string FormatMoney(int64 n, bool fPlus)
     int64 remainder = n_abs%COIN;
     string str = strprintf("%"PRI64d".%08"PRI64d, quotient, remainder);
 
-    // Right-trim excess 0's before the decimal point:
+    // Right-trim excess zeros before the decimal point:
     int nTrim = 0;
     for (int i = str.size()-1; (str[i] == '0' && isdigit(str[i-2])); --i)
         ++nTrim;