Remove declarative api from chemistry

Author: manoelmarques

chemistry/h2_excited_states.ipynb

@@ -26,22 +26,7 @@
      "text": [
       "Couldn't find cython int routine\n",
       "Couldn't find cython int routine\n",
-      "Processing step __\b\b 0"
-     ]
-    },
-    {
-     "name": "stderr",
-     "output_type": "stream",
-     "text": [
-      "/Users/manoel/anaconda3/envs/Qiskitenv/lib/python3.7/site-packages/pyscf/scf/chkfile.py:31: H5pyDeprecationWarning: The default file mode will change to 'r' (read-only) in h5py 3.0. To suppress this warning, pass the mode you need to h5py.File(), or set the global default h5.get_config().default_file_mode, or set the environment variable H5PY_DEFAULT_READONLY=1. Available modes are: 'r', 'r+', 'w', 'w-'/'x', 'a'. See the docs for details.\n",
-      "  with h5py.File(chkfile) as fh5:\n"
-     ]
-    },
-    {
-     "name": "stdout",
-     "output_type": "stream",
-     "text": [
-      "20 --- complete\n",
+      "Processing step 20 --- complete\n",
       "Distances:  [0.5   0.525 0.55  0.575 0.6   0.625 0.65  0.675 0.7   0.725 0.75  0.775\n",
       " 0.8   0.825 0.85  0.875 0.9   0.925 0.95  0.975 1.   ]\n",
       "Energies: [[-1.05515979 -1.07591366 -1.09262991 -1.10591805 -1.11628601 -1.12416092\n",