public static boolean isNCNameStart(int c) {
        return c < 0x10000 && (CHARS[c] & MASK_NCNAME_START) != 0;
    }
Returns true if the specified character is a valid NCName start
character as defined by production [4] in Namespaces in XML
recommendation.

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