Move ResponsiveController into the js/ package hierarchy.
Update ArrayProperty to work with packaged subTypes, via FOAM.lookup.
Cleanup UpdateDetailView to use more concise imports and remove redundant properties.
Make the openComposeView method used in saturn/gmail apps be context aware.
Update apps/gmail/main.html to arequire MGmail before using it.
Add two pane support to mgmail.
Modernize MGmail
Merge branch 'master' of github.com:foam-framework/foam
Add foam.ui.md.TwoPane model.  An AppController view that splits the view into two panes.