unittesting and readme update

propka.py

@@ -1,4 +1,4 @@
-#!/usr/bin/env python3.1
+#!/usr/bin/python3
 
 import string,re,sys,os,math
 import Source.lib, Source.molecular_container 
@@ -9,7 +9,7 @@ def main():
     """
     # loading options, flaggs and arguments
     options, pdbfiles = Source.lib.loadOptions()
-    
+
     for pdbfile in pdbfiles:
         my_molecule = Source.molecular_container.Molecular_container(pdbfile, options)
         my_molecule.calculate_pka()