DateAndTime: modify timezone set
display: support switch displaymode
grub2: dispatch theme scheme, dark and bright
grub2: fix dbus import path
makefile: add grub2
DateAndTime: add zone city list
grub2: update grub if cache file is not exists
grub2: update copyright info
grub2: update test code
power:adapted useful functions from power plugin of gsd
power:remove Makefile
power:respond to battery critical percentage event
power:deal with low battery event at startup and prompt for just once
power:added power settings schema file
power:using new schemas,dealing with idle and low power event,prompt for low power
power:added power schemas file
power:fixed the glib SIGSEGV when calling c code from golang by calling c code before calling other golang glib/dbus binding function
power:added files