Fix icons overflowing status bar view in center clock and date layout

Based on @maxwen commits
1 - https://github.com/maxwen/frameworks_base/commit/5b4d7714ea5fcc493712b569f456f655bf696076
2 - https://github.com/maxwen/frameworks_base/commit/5b4d7714ea5fcc493712b569f456f655bf696076
3 - https://github.com/maxwen/frameworks_base/commit/b5f7820e50fd03522b5462777779a4520594c796

All credits goes to him.

Change-Id: I23be4b166941159d6b5891442bfcefa3678a0603
Remove dead code.

This hasn't been used since at least 2011, and we're no longer
shipping the data supporting it either.

Change-Id: Ibe42057650b49794c65d6f0d54ed7a492f3b594b
DocumentsUI: Add a standalone File Manager

This commit adds a standalone mode to the DocumentsUI, to let
it act as a file manager/explorer.
You can browse your storage contents, open files, and delete them,
as well as do everything that the DocumentsUI can do (ie. sort
by name/size/type, list and grid view, recents, search, ...).

This gives us a consistent file browsing UX accross all apps
that uses the new documents API.

Change-Id: If73a3c100f010bdb766c843976d4fd3573ea805c
Fix Icon size in DocumentsUI

For XXHDPI devices if you go into Settings/Display and Notification light and select a custom value (application) you will see a GIANT icon.

Before - http://i.imgur.com/DRkua3T.png

After - http://i.imgur.com/f7xW4tY.png

Change-Id: Ia355bddc515906134c8b3b4e67d381aaacceec78