small fixes

libhtmlpp::HtmlString &libhtmlpp::HtmlString::operator=(const char *src){

    clear();

    std::copy(src,src+strlen(src),_Data.begin());

    std::copy(src,src+strlen(src),std::insert_iterator<std::vector<char>>(_Data,_Data.begin()));

    return *this;

}

libhtmlpp::HtmlString & libhtmlpp::HtmlString::operator=(std::string *src){

    clear();

    std::copy(src->begin(),src->end(),_Data.begin());

    std::copy(src->begin(),src->end(),std::insert_iterator<std::vector<char>>(_Data,_Data.begin()));

    _Data.push_back('\0');

    return *this;

}