pyramid_layout breaks with latest pyramid_mako

[blaflamme]

Here's the relevant traceback

File "/path/to/pyramid_layout-0.8-py2.7.egg/pyramid_layout/config.py", line 359, in register
    template = helper.renderer.implementation()
pyramid.exceptions.ConfigurationExecutionError: <type 'exceptions.AttributeError'>: 'MakoLookupTemplateRenderer' object has no attribute 'implementation'

Latest versions of pyramid_mako and pyramid_jinja removed this private api. Same error apply for add_panel, not just add_layout.

[rnortman]

Pull request #25 submitted which fixes this issue.

[blaflamme]

@chrisrossi tested in multiple apps and it seems fine. Merge and release when you have time, pyramid_mako was released during sprints :)

[chrisrossi]

@blaflamme Did you look at #27 or #25?