linted redundant backslashes for line continuations
removed double spacing
Tidy up pep8 violation in doctest
bugfix: dynamic routes no longer cache references to view methods

Fixes a bug with dynamic routing, where the bound methods of view
classes were cached on the route object, meaning the same view class
instance would be used for all requests. For example:

    class MyViews(object):

        __routes__ = [Route('/', GET, 'myview')]

        def __init__(self, context):
            self.context = context

        def myview(self):
            ...

    app = FrescoApp()
    app.delegate('/<context:str>', MyViews, dynamic=True)

The routing system would correctly instantiate instances of MyViews per
request - however, the string viewspec ('myview') would be resolved to a
bound method on the first request only and reused thereafter, meaning
it would always be called with the same MyViews instance.