This creates:
1) An `xtask' command that allows someone to compile individual apps
without compiling the entire image (note that this is required because
xtask generates files that contain gam context names, and if you just
do a regular `cargo build' building the app will fail)
2) A python file app_server.py that acts as a server to give the
app-loader a list of the apps and actually send it the
3) A basic UX that allows app-loader to set the server, get the list
of apps, and load apps.
Currently, this mostly works, except that there is some random
`ShareViolation' when the app-loader loads the app.
