Rockbox

This patch is to replace #696904 which was only a first
strike.

With this patch, time/date-values are stored in the
config_block from [0xa1] to [0xa7], which is saved on
the disk.

After a power-loss, the values are read from the
config_block and written to the RTC, so there is
immediately a defined status of the clock.

If the config_block is invalid, the time is generated
from the APPSVERSION-string, which is build at
compile-time.

So:
If you just change the batteries, the last time on disk
will be set,
if you change the CONFIG_VERSION, the time you compiled
your ajbrec.ajz will be set.

ToBeDone: DayLightSaving (DST)
It would be nice to have one key to change between
summer/wintertime.
My idea:
in "General Settings - System - Time/Date" push PLAY to
toggle between summertime/wintertime (the hour-value
will be set also).
All I need is a place to store the value of "DST". Why
not using
a free bit in the RTC-Config_Block?

...stay in touch...