Re-packaged with setuptools for standard installation

* 'python setup.py install' will install
  - a package 'propka' (which contains everything that 'Source' contained
    in the original distribution)
  - an executable script 'propka31' (which is identical to the original
    'propka.py' script but it is automatically generated via the setuptools
    mechanism; it uses propka.run.main().
* 'pip install' will also work
* the README.md file was changed to reflect the alterations
* metadata in the setup.py file was added

NOTE: The licence is still unclear!

propka/determinant.py

@@ -0,0 +1,29 @@
+
+from __future__ import division
+from __future__ import print_function
+
+class Determinant:
+    """
+        Determinant class - set up for later structurization
+    """
+
+    def __init__(self, group, value):
+        """
+        Contructer of determinant object - simple, but helps in creating structure!
+        """
+        self.group = group
+        self.label = group.label
+        self.value = value
+
+        return
+
+    def add(self, value):
+        """
+        adding a value to determinant
+        """
+        self.value += value
+
+        return
+    
+    def __str__(self):
+        return '%s: %8.2f'%(self.label,self.value)