Use --delay-updates on rsync upload to minimize time of inconsistency in the repo

During the rsync operation, package lists could go out of sync with the
.ipk files, or a mirror might be pulling an incomplete list of files.
To reduce the chance of this happening, let rsync put all updated files
into place at the end of the transfer

Signed-off-by: Felix Fietkau <[email protected]>

Add .gitignore

Signed-off-by: Jo-Philipp Wich <[email protected]>

Add relocatable buildbot.tac files

Signed-off-by: Jo-Philipp Wich <[email protected]>

Canonicalize home_dir, download key-build.pub as well

Signed-off-by: Jo-Philipp Wich <[email protected]>

Move config.ini to config.ini.example and make paths relative

Signed-off-by: Jo-Philipp Wich <[email protected]>

Remove intermediate master directory

Signed-off-by: Jo-Philipp Wich <[email protected]>

Fix typos in example configs

Signed-off-by: Jo-Philipp Wich <[email protected]>

Add buildmaster configurations

Signed-off-by: Jo-Philipp Wich <[email protected]>