SVN repo structure

[Boyan Sheytanov]

Hey there!

I was browsing the svn repo these days and found some issues that
might need to be fixed:
 * In incubator, there are empty folders engage-client and
engage-sketches that are probably no longer needed.
 * In scratchpad/decapod we should probably add the dserver.py file
that resides in the Google code repo.
 * We should probably move decapod stuff from scratchpad to incubator
since we have to deliver the Capture interface pretty soon.
 * In fluid, there are two folders with externals that point to the
same place (fluid-all and fluid-build-all). There's probably a reason
for this, but I couldn't get it. Only one of these might remain.
 * In fluid, we probably need a separate folder for the engage stuff,
with an external pointing to Infusion in it. See
http://issues.fluidproject.org/browse/ENGAGE-168.

I'm not really sure if these make sense to you, but I think with these
changes the repo structure will be much more clear. There are probably
other issues that need to be resolved as well (mainly related to
externals).

Greetings,
Boyan