add some minimum description for base classes

bfps/base.py

@@ -25,6 +25,10 @@ import h5py
 import bfps
 
 class base(object):
+    """
+        This class contains simulation parameters, and handles parameter related
+        functionalities of both python objects and C++ codes.
+    """
     def __init__(
             self,
             work_dir = './',

bfps/code.py

@@ -26,6 +26,10 @@ import bfps
 from bfps.base import base
 
 class code(base):
+    """
+        This class is meant to stitch together the C++ code into a final source file,
+        compile it, and handle all job launching.
+    """
     def __init__(
             self,
             work_dir = './',