new console feature: web-load

In preparation for others using my semantic agent console, I implemented the web-load function. Before, you could only load local sw files, now you can load remote ones.

Simply enough:

$ ./the_semantic_db_console.py
Welcome!

sa: web-load http://semantic-db.org/sw-examples/methanol.sw

In the process it downloads the file, saves it to disk (first checking if that filename is already taken) and then loads it into memory. BTW, currently it uses the user agent string: "semantic-agent/0.1"

Now, what if you want remote sw files to be in a different directory than your local sw files? Well, we have had code in there for a long time that can handle that. Here are a couple of lines from the console help string:

  files                        show the available .sw files
  cd                           change and create if necessary the .sw directory
  ls, dir, dirs                show the available directories

Finally, I hate to say this, but a big warning about loading remote sw files! Currently there is an injection type bug when loading superpositions that contain compound function operators. This makes fixing the parser somewhat critical!

Heh, that wasn't an issue previously, since I was the only one using sw files. Now we are on github it is rather more important.

And I should also note that loading sw files into memory can take an arbitrary amount of time, depending on what computation it is trying to do. eg, a while back I had a simple 2 line sw file that took about 1 week to finish. It was a similar[op] calculation on a big data-set.

Update: I fixed the above parser bug. Thanks parsley.