[backend] remove dst parameter from update_dst_full()

It is always "$gdst/$packid"...
[backend] simplify fctx_add_binary_to_full to no longer use dst
[backend] detect and fix out of sync bininfos when rebuilding the full tree
[backend] do not fetch imported binaries when getting the old package build result
[backend] add an easy way to force a full tree rebuild
[backend] fix _volatile cleaning if a volatile binary gets replaced
[backend] remove typo exposed by last commit
[webui] avoid crash on invalid tracker in patchinfo editor
[api][backend] log build duration

and use it for job progress estimation
[backend] fix buildhistory query with duration time
[webui] accept extra error handling in code check
[webui] Better management of usernames in markdown

 * Users with a dash (like 'yast-team') are now managed properly.
 * Users with two underscores (like '_nobody_') are not enclosed in <em> tags
[backend] report filename of bad files if the db is corrupt
[backend] implement first steps of package tracking
[backend] ignore bad entries if the gbininfo is out of sync

Otherwise we may die if gbininfo references vanished packages.
[backend] rework dbgsplit code, make packtrack available to plugins

- packtrack needs to be mixed
- deleterepo needs the repoinfo for subdir
[backend] modernize publisher to use store/retrieve from BSUtil
[backend] small code cleanups
report patchinforef in packtrack data

also report supportstatus for testing purposes
[api] fix migration numbering