Solute-solvent clusters

Changed <ul> <li>Reorganized <code>solute</code> and <code>solute.solvent</code> to <code>heterogeneous</code> and <code>homogeneous</code>.</li> <li>Moved selected ABCluster structures into the <code>abc</code> folders instead of having them separate.</li> </ul> Added <ul> <li>Methanol 20mers from Pires &amp; Deturi (DOI: <a href="https://doi.org/10.1021/ct600348x">10.1021/ct600348x</a>) and Yao et al (DOI: <a href="https://doi.org/10.1063/1.4973380">10.1063/1.4973380</a>).</li> <li>Packmol generated structures of 30h2o, 112h2o, 140h2o, 30mecn, 39mecn, 30meoh, 50meoh, and 62meoh.</li> <li>ORCA MP2/def2-TZVP energy+gradient calculation of Yoo et al. boat-b 16mer.</li> <li>Methanol 4-6mer minima from Boyd et al. (DOI: <a href="https://doi.org/10.1021/ct6002912">10.1021/ct6002912</a>) with MP2/def2-TZVP engrads.</li> <li>Acetonitrile 4-6mer minima from Malloum et al. (DOI: <a href="https://doi.org/10.1002/qua.26222">10.1002/qua.26222</a>) with MP2/def2-TZVP engrads.</li> <li>Water 16mer minima from Yoo et al. (DOI: <a href="https://doi.org/10.1021/jz101245s">10.1021/jz101245s</a>) with RI-MP2/def2-TZVP engrad.</li> <li>Water 4-6mer minima from Temelso et al. (DOI: <a href="https://doi.org/10.1021/jp2069489">10.1021/jp2069489</a>) with MP2/def2-TZVP engrads.</li> <li>20 Angstrom box of water from GROMACS solvate.</li> </ul> Removed <ul> <li>Moved 12h2o.su.etal monomers, dimers, and trimers to <a href="https://github.com/keithgroup/mbgdml-h2o-meoh-mecn-engrads">another repository</a>.</li> </ul>