Extract templates and diazo rules to proxybase app

- proxybase/diazobase.xml : default diazo rules included in all diazo
files
- proxybase/templates/proxybase.html : default template for proxy apps

Signed-off-by: Gustavo Jaruga <darksshades@gmail.com>
Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Add boostrap-colab to colab menu, refactor utils to proxybase

-Proxybase is now an abstract app

Signed-off-by: Gustavo Jaruga <darksshades@gmail.com>
Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>