Modification regarding backwards incompatibility with Mako templates in Pyramid 1.5

Added note in the beginning (with a link) regarding the need to install support for Mako templates with an add-on.

Also added a line of code to the task.py file to enable Mako templating support
Added reference to pyramid_mako add-on

Added reference and code necessary for enabling the pyramid-mako add-on (required for Pyramid 1.5+)
Added inclusion of pyramid_mako add-on

Added the config statement to include the pyramyd_mako add-on (required for Pyramid 1.5+ and backwards compatible)
Merge pull request #47 from jorgeblanco/patch-1

Modification for backwards incompatibility with Mako templates in Pyramid 1.5