V1.5.0 stabil no bootloaderfiles in the release files

[hrenz]

for update only
first flash the bootloader to the latest Version

but at the V1.5.0 Release files there is no bootloader file
think, normal user need it

[mawzthefinn]

1.5 uses the most recent bootloaders (1.4.15 for most systems, 1.4.17 for X12S)

[Bertrand Songis @ FrSky]

We only release a bootloader when it is really needed. Ethos Suite shows the right version of all components, including the bootloader.