Cleanup commands.c
Added loadpic function and made seperate return value enum
Move beacon packet generation to a function and create a beacon command
Check packet length for incoming commands
Advance picture number after each picture
Added erase images command
Added handler for SUB_EV_SPI_ERR_BUSY event
Changed handling of readpic command
Change CMD_IMG_READ_PIC to only read a single image block
Added pictlist command
Dont clear picture slot on savepic command
In loadpic block is buffer+2
CRC len does not need to be added to SPI data
Added time stamp to images