Move definitions to specific header.
Move priorities management to pkg_universe.
Move more code.
Split universe handling function.
Fix jobs processing.
Add find utilities.
Rework candidates selection.
Fix cudf module.
Rework conflicts.
Rename pkg_conflicts as it is jobs part.
More rework.
Fixes for jobs code.
Refactor names.
Ignore sigpipe to avoid resources leak.
Read lock is now no-op unles READ_LOCK option is turned on.
Refactor update.
EORDER.
Fix incremental repo updates.

Insert should be accompanied with `OR REPLACE` for packages since we
want to upgrade packages information in repo.
Add a rootfd to simplify handling of relocation
Add sha256_fileat function