public static boolean isXML11NameStart(int c) {
        return (c < 0x10000 && (XML11CHARS[c] & MASK_XML11_NAME_START) != 0)
                || (0x10000 <= c && c < 0xF0000);
    }
Returns true if the specified character is a valid name start
character as defined by production [4] in the XML 1.1
specification.

@param c The character to check.
stroom-util/src/main/java/stroom/util/xml/XML11Char.java