Clean up imports in DC, move data to forward folder. clean up init statements.

SimPEG/forward/Data.py

@@ -0,0 +1,20 @@
+from SimPEG import utils
+
+
+class SimPEGData(object):
+    """Data holds the observed data, and the standard deviations."""
+
+    __metaclass__ = utils.Save.Savable
+
+    std = None    #: Estimated Standard Deviations
+    dobs = None   #: Observed data
+    dtrue = None  #: True data, if data is synthetic
+    mtrue = None  #: True model, if data is synthetic
+
+    def __init__(self, prob, **kwargs):
+        utils.setKwargs(self, **kwargs)
+        self.prob = prob
+
+    def isSynthetic(self):
+        "Check if the data is synthetic."
+        return self.mtrue is not None