Revert: Add time-context headers to the notification header

Revert "adjust header hours"

This reverts commit feb807f135aa14f67b3f9703d42b12262a1a33b7.

Revert "Re-do contextual notification header images"

This reverts commit dbf160dcbf9b2f6b5cabcb75c558db00045b1992.

Revert "Add evening time to header"

This reverts commit 6376d7496922c1f86badae4a05751f7dd12ad184.

Conflicts:
	core/java/android/provider/Settings.java

Change-Id: I8b8984e8eef0eb92d19ef89035659cb424ab6e71

Revert "SystemUI: Fix notification header disappearing on tablets"

This reverts commit 82ab13c6dfcb3193b487d6371390fdefa904cec1.

Revert "[1/2] SystemUI: Add time-context headers to the notification header"

This reverts commit 3eb87509a04bdaa2844ad3543e4bc70c3a99782f.

Conflicts:
	core/java/android/provider/Settings.java
	packages/SystemUI/src/com/android/systemui/statusbar/phone/PhoneStatusBar.java

Change-Id: Icd713d6670f3393b27c8868816f73d9f92c8d758