Bug 905606 - Gaia for bug 892212 Support for BT inline pairing User

According to UX spec., the patch is supporting for Bluetooth inline pairing user story.
https://bugzilla.mozilla.org/show_bug.cgi?id=892212#c13
* Remove custom value selector(older paired devices list)
* Add device list component which is almost same with settings app::bluetooth(without toggle bluetooth, visible, and rename device's name)
Note: The patch is still WIP.