Patched the appserver to not overwrite the user's Python path (and instead just append to it)

Also I overwrote the catches that kept Python from opening some files with 'open'
Added test example to modeleditor.py for Brian to look at
Simplified the example
Aha! So I got a fix for the import dolfin problem.

The Google App Engine SDK overwrote the sys.platform variable which was used for import of another library.

Still dolfin can't read meshes correctly though
Woo! It seems that the dolfin read mesh works as well too!
Merge pull request #189 from StochSS/fiximports

Fiximports