add checks when reading QEQ parameter file to avoid segfaults and memory...

    nwords = atom->count_words(line);

    if (nwords == 0) continue;

    // words = ptrs to all words in line

    nwords = 0;

    words[nwords++] = strtok(line," \t\n\r\f");

    while ((words[nwords++] = strtok(NULL," \t\n\r\f"))) continue;

    itype = atoi(words[0]);

    chi[itype]   = atof(words[1]);

    eta[itype]   = atof(words[2]);

    gamma[itype] = atof(words[3]);

    zeta[itype]  = atof(words[4]);

    zcore[itype] = atof(words[5]);

    // must have 6 parameters per line.

    if (nwords < 6)

      error->all(FLERR,"Invalid fix qeq parameter file");

    // words = ptrs to first 6 words in line

    for (n=0, words[n] = strtok(line," \t\n\r\f");

         n < 6;

         words[++n] = strtok(NULL," \t\n\r\f"));

    itype = force->inumeric(FLERR,words[0]);

    if ((itype < 1) || (itype > atom->ntypes))

      error->all(FLERR,"Invalid fix qeq parameter file");

    chi[itype]   = force->numeric(FLERR,words[1]);

    eta[itype]   = force->numeric(FLERR,words[2]);

    gamma[itype] = force->numeric(FLERR,words[3]);

    zeta[itype]  = force->numeric(FLERR,words[4]);

    zcore[itype] = force->numeric(FLERR,words[5]);

  }

  delete [] words;

}