Implement dotted names for URL endpoints

[justquick]

It makes a lot of sense to change the way endpoints (the names of the functions / URL rules) are handled to also take the module name into account. Right now the function name is the URL name, but imagine you have a large applications consisting of multiple components. In that case, it makes a lot of sense to use dotted names for the URL endpoints.

[mitsuhiko]

For larger applications there are more obstacles than just dotted names. Not sure if it makes sense to consider dotted names.