Reduce image size to 3800MB
Created by: SunilMohanAdapa
Closes: #73 (closed). The current images don't fit on many 4GB SD cards and also on the internal eMMC of beaglebone which has 386148288 bytes in one case.
Many 4GB SD cards seem to have less than 4000000000 bytes available on them. This could sometimes be because of bad sectors or but also happen on new disks.