public static String xmlEscape(String string, boolean isAttribute, boolean escapeLowAscii, char stripCharacter) {
        return xmlEscape(string, isAttribute, escapeLowAscii, null, (int) stripCharacter);
    }
Replaces the characters that need to be escaped with their corresponding character entities.

@param string the string possibly containing characters that need to be escaped in XML
@param isAttribute whether the input string to be used as an attribute
@param escapeLowAscii whether ascii characters below 32 should be escaped as well
@param stripCharacter any occurrence of this character is removed from the string
@return the input string with special characters that need to be escaped replaced by character entities
vespajlib/src/main/java/com/yahoo/text/XML.java