[Dev] CPIA Script update

[Donn Denman]

Today a few changes were made to CPIA Script that I want to tell you  
about.

1) Security is much tighter on scripts now.  You can't share the  
Scripts collection, or individual scripts.  You can't even change  
scripts that you did not create.  Under normal circumstances you  
don't even see scripts -- you add the Scripts collection to the  
sidebar through a Test menu item.  There isn't even any UI for  
creating a new script, except for a built-in script that creates one  
when you press the F12 key.

2) In the past we've provided pre-defined "helper functions" for  
scripts to make it easier to script Chandler.  We're in the process  
of moving to a model where things that are hard to do in Chandler get  
simplified in Chandler, instead of providing helper functions.  In  
the current implementation the helper functions have been gathered  
into a few proxy objects that extend the functionality of existing  
Chandler objects, in the way we'd like to extend Chandler itself in  
the future.  Consider these proxies a proposal for how we might make  
Chandler's API simpler.  Oh, and you can get these same facilities  
from anywhere within Chandler itself by just importing * from the  
scripting parcel.  See osaf.framework.scripting.txt for a doctest  
file that provides some documentation for these proxies.  The  
CpiaScriptUserGuide wiki will be updated soon.

3) Example scripts now live in osaf.app.scripts.  If you write handy  
scripts, you can add them to our repository by putting your script in  
that directory, and modifying the parcel to load it.  I hope to build  
some of our acceptance tests as scripts sometime soon.

- Donn