Method remove

include/matplotlibcpp.h:2471–2480

definitely remove this line

    // definitely remove this line
    void remove() {
        if(line)
        {
            auto remove_fct = PyObject_GetAttrString(line,"remove");
            PyObject* args = PyTuple_New(0);
            PyObject* res = PyObject_CallObject(remove_fct, args);
            if (res) Py_DECREF(res);
        }
        decref();
    }

    ~Plot() {
        decref();