Bootloader example files for the SR5E1E5

Hi

Do any example bootloader files exist for the SR5E1E5 micro series.  I can see that there are flash examples in the ESDK area of the StellarStudio, but I cannot find any bootloader example files.

If there is no example code, then are there any application notes on the process for creating a bootloader that can program the Flash?

Many thanks in advance.