Updated version to 1.2.3.

CHANGES.md

 Changes
 =======
 
-WIP
----
+1.2.3
+-----
 
 * Updated protonation of nitrogen, oxygen, and sulfur atoms to be compatible
   with the latest version of RDKit, which broke backwards compatibility.

README.md

-Dimorphite-DL 1.2.2
+Dimorphite-DL 1.2.3
 ===================
 
 What is it?
@@ -34,7 +34,7 @@ usage: dimorphite_dl.py [-h] [--min_ph MIN] [--max_ph MAX]
                         [--smiles_file FILE] [--output_file FILE]
                         [--label_states] [--test]
 
-Dimorphite 1.2.2: Creates models of appropriately protonated small moleucles.
+Dimorphite 1.2.3: Creates models of appropriately protonated small moleucles.
 Apache 2.0 License. Copyright 2018 Jacob D. Durrant.
 
 optional arguments:

dimorphite_dl.py

@@ -137,7 +137,7 @@ class ArgParseFuncs:
         :return: A parser object.
         """
 
-        parser = MyParser(description="Dimorphite 1.2.2: Creates models of " +
+        parser = MyParser(description="Dimorphite 1.2.3: Creates models of " +
                                       "appropriately protonated small moleucles. " +
                                       "Apache 2.0 License. Copyright 2018 Jacob D. " +
                                       "Durrant.")