Add ZRAM support to vanir.cfg

Set the default value to 1 if the config file
doesn't have ZRAM stuff in it (allows previous
configs that didn't have this to live-on, while
adding a default value to people's existing vals)

Added vanir config menu for memory management.

the zram script is straight from Imoseyon's LK,
modified to use a non-LK-ramdisk busybox location

Change-Id: Ib647338e2e6ca5108f572bdc6b0351263c362b75