Initial stub for web based UI using browserify

Use browserify to compile the onepass JS lib to a bundle file
for use in a web-based UI
Get a stub web UI working

This stub authenticates with Dropbox, displays a list
of items in the vault, allows the user to unlock
the vault with a password and then shows item
details as JSON when selected.
Add the Dropbox key for the test UI

This key is configured for use with localhost:8000
Add a make target to update the built version of the app on Github pages

This checks out the gh-pages branch in a copy of the repo, copies
the current build to that repo and creates a commit with the changes,
then pushes the result back to the gh-pages branch.
Redirect to an https:// location when accessing the app from a non-localhost host

For security the OAuth login flow requires the redirect URI to be an
HTTPS endpoint. We also want to ensure that the user is receiving the
correct copy of the app.
Point the Dropbox dependency download to a forked version with a Browserify fix

Set the dropbox dependency to a forked version
with the fix in https://github.com/robertknight/dropbox-js/commit/4890afb8787e05672f59851ad4275a36343ff1a2
for compatibility with browserify
Fix make not rebuilding when web UI sources change

Fix typo in webui source file dependency list
WIP - Add react dependency and stubs for UI views
Add initial outline of the item list UI

Display list of items with their associated locations
and icons.
Update the publish-app make target to clear the existing app/ directory
Item list layout improvements

 - Keep the search bar visible when the list is scrolled
 - Display only the item domain in the list
 - Use Helvetica Neue as the default UI font with fallbacks to Segoe UI and
Add viewport tag for mobile
Add prefixed flexbox CSS directions for iOS compatibility
Initial work on unlock pane and details view

 * Unlock the vault after entering the master password
   and clicking the 'Unlock' button

 * Add selected item to list view state and propagate
   selected item to item details view
Enable unlocking vault with enter key and hide unlock pane after unlock

Make the unlock pane a form so that it can be submitted
using keyboard input and hide it after the vault is successfully
unlocked.
Add a missing unit test suite file to Git
Merge branch 'master' into rob-web_ui

Merge automatic submodule and npm module update
on make from master.