[plt-scheme] function for reading text from Scheme files

Robby Findler wrote:

> Also, I think Eli has a script that does this and is more robust.

replying to Danny Yoo who wrote:

>> Geb wrote a message while back asking how to get text out of PLT-enriched 
>> Scheme file.  One way to do it is to use the Framework functions to get at 
>> an interesting editor, and then call snip-specific methods on that editor.

It would be nice to have a way of doing this without running mred (which 
Eli's script does), because that requires a connection to an X server. 
We'd like to be able to translate snips, comment boxes and other 
non-textual things that students stick into programs, using a script 
which will run in a standard terminal window. So I throw this out as a 
challenge to the community. --PR