The 'a' package is now more preferred which actually makes more
sense.

Enabled when all attempts to satisfy a name failed, we know that we
can ignore all decisions until we find a decision affecting the name
we wanted to satisfy.

to be functional when backtracking

We can't just use the primary name, as that would mess up
backtracking. We need to record the name which caused the name
to get considered - that way the right last_touched_decision is
used on backtracking.

 * push_decision expects to always get the package primary 'name'
   as apk_name. ASSERT that and fix problem cases.
   (though - this might need to be reverted, and store the non
    primary name in apk_decision instead to accomodate for better
    backtracking optimizations)
 * fix error reporting of virtual package names
 * make 'assign_name' errors soft. the incorrect packages just are
   no longer consider instead of aborting whole calculation.
 * fix backtracking of virtual packages that are not depended
   directly

Print name of package and void double "ERROR"

fixes #1396

fchmodat does not support this flag - symlinks do not have permissions.

Sysadmin probably does not expect us to not follow symlinks either:
if /var -> /mnt/foo/var, we should be making sure the permissions
and ownership is correct on the target directory, not on the symlink.

Since fchmodat never returned ENOENT with AT_SYMLINK_NOFOLLOW, this
also fixes directory re-creation if it does not exist. fixes #1348.

Add new 'd' flag for it.

If a directory has protection mask, but does not exist in db, we
do not handle it right unless we calculate the protection mask by
hand, or create temporary db dir entry for it. For simplicity create
always the db dir entry -- depending on audit type we likely need
to create it anyway. This commit also caches the db dir entry in the
audit tree context to avoid duplicate lookups. ref #1241.

Use the paths' protection mask where available instead of the parent
paths'. ref #1241

- makes -v option useful
- makes --origin --quiet --exact useful for piping and scripting
- makes the default output more readable

ref #1122

Do not print version numbers or compare result char when in quiet
mode. This makes the output suitable for be used in scripts or pipes.

For example:

  # Upgrade all packages that matches a given regexp
  apk version --limit '<' --quiet | grep $regexp | apk fix --reinstall

  # Delete all packages that are removed from repository
  apk version --limit '?' --quiet | xargs apk del

This makes it possible to differ between downgradable packages (-l '<')
and unavailable in repos (-l '?').

fixes #1116

Fixes --recurse during audit.

fixes #1072

fixes #1069

apk_name_state is now quite small; and we avoid overhead of two
pointers (+ malloc overhead) when we just make it part of apk_name.
It also fixes some problems (that got introduced) where apk_name_state
was not allocated.

Solver will now never report partial solution where a conflict
constraint is not satisfied. The is because with --force we might
install the partial solution; and if conflicted packages were to
be installed we might have extra trouble.