[Developers] Where is the canonical version of the Acre documentation?

[Tom Morris]

OK, this is driving me nuts.  There are a bunch of different places to
look for Acre documentation and each one says something slightly
different or has a piece of the puzzle that's not in one of the
others.  One place has tutorials but they don't use any recent
facilities, another has a tutorials section, but it's empty.  Some
things I can't find anywhere.

What is most up-to-date?  What is most complete?  (Hopefully these two
questions don't have different answers)

For bonus points:

- Where can I find a conceptual overview, especially what gets
executed where (server vs client) in which order?
- What does the "def" attribute in the following do? <acre:block
def="renderTask(taskData, isIPhone)">
- Where can I find an example of simple paged output using Acre?

Tom