changed local app store to be global

Ignore-this: 356bedd4b107d4fe1c983eab4fe09895

I had the local store be per app, but changed it to be global.
This should make the the local store more powerful (and potentially more dangerous)

darcs-hash:20140128192943-c21fe-2b5950aad47b9a46c9e58d1209783d0375cad5d0
added magical support for both app data and local data

Ignore-this: c5e1971df2de32f0a3435ed2d27fa56e

apps can now save data per app, and data globally using the disk store api.
app data is sent with the application code, but local data stays local.

The idea eventually is to provide a way to store data and files packaged with the app
that get sent with it.

darcs-hash:20140129043545-c21fe-25aa7cbb16688f31392a2b99bededafa763dfc2c