[api] minor code cleanup
[api] skip local channel repos on branching

Do not copy repostories used for local channel containers when branching from a project
[api] check also the local target of a channel
[backend] do not dispatch aggregates as well

Extends commit #faba9ef0
[ci] test collected binaries in kgraft case
[api] support maintenance incident request for kgraft case

Transfer channels and link targets to GM or incident projects.
This allows to build against former incidents or even GM version
for generating patches
[api] gitignore public/assets
[api] support submission of kgraft sources to code stream project

yes, ugly. this is what you get when a conceptional solution is required
the day before vacation ...
[api] fix rollback when user has modified tracking data
[api] Do a migration in a different way

we do not modify, but entirely recreate the tables here, because there is
an issue in (older?) MySQL version which corrupt the database when modifing
these indexes. Since this is just indexed data based on sources we do not want
to go with any risk
[api] avoid conflicting flags in projects

Do not copy a flag if it has been set with same specification level.
No matter if it is an enable or disable one.
[doc] Add update notes to 2.6
[ci] log scheduler output
[backend] fix %N updatinfo id replacement in incident

Still broken in test case, because backend stores only one target of the channel
in .channelinfo. Therefore it does not see the right target with id_template when
generating the temporary updateinfo.xml
[api] implify code
tidy up
merge problem fixed