Test-multiple

[Robert Goldman]

Faré ---

Would you please add some comments to test-multiple?  I got a failure on 
that with MKCL under jenkins on linux, but cannot replicate that failure 
running it myself.

There's no comment saying what this is supposed to test, other than the 
name, which suggests that it's about testing where there are ... 
multiple systems defined (incorrectly) in one .asd file? the same 
systems defined in multiple .asd files?

The test checks to make sure (I believe) that a variable is not rebound 
when we ask to reload a system, but not how this pertains to correct 
ASDF function.

thanks!
r