'**SUMMARY**
Given a tolerance, test the blob against the rectangle distance to see if
it is rectangular.
**PARAMETERS**
* *tolerance* - The percentage difference between our blob and its idealized bounding box.
**RETURNS**
Boolean True if the blob is withing the rectangle tolerage, false otherwise.
**EXAMPLE**
>>> img = Image("lenna")
>>> blobs = img.findBlobs(128)
>>> if(blobs[-1].isRecangle() ):
>>>     print "it is hip to be square."'

def isRectangle(self, tolerance=0.05):

    if (self.rectangleDistance() < tolerance):
        return True
    return False
