Move isolatable bluetooth code to SettingsLib

Move the non-ui bluetooth control/tracking code to SettingsLib so
that it can be shared with others.

Mostly just move classes to frameworks/base/packages/SettingsLib,
however a few things had to move around.
 - Dock handling had to move back to code still in settings
 - Local preference related code had to be moved back to settings
 - Added an error flow from SettingsLib to Settings

Depends on I69fd888362c6dbb325f6113b32c4b15cc6a23a41
Bug: 19180466
Change-Id: Ie57fe26a27bbb0adc2ef69e042a05c7290c6a52a