Add option to disable searchbar in recents [1/2]

Coded by yashade2001 <yashade2001@gmail.com>
Cherry-picked from Project D.I.S.C.O.
Thanks to TheMrcool212 for his help.

NOTE: This commit needs CM's helper class for SwitchPreference.
Add that class to somewhere and change display_settings.xml, line 36...

Change-Id: Ibfb2bb0b397554d01349038d3cd1961a6e8288ee
Signed-off-by: Yashar Ahmedizadeh <yashade2001@gmail.com>