fixes #3371

Apk used to reset directory permissions always, but this is undesirable
if user has modified the permissions - especially during tmpfs boot.
Though, it is desirable to update the permissions when packaging has
changed permissions, or a new package is installed and the merged
permission mask / owner changes.

Thus the new code updates the permissions only if:
 1) We are booting and directory is not in apkovl
 2) The directory is modified by a package install/remove/upgrade
 3) The filesystem directory permission matched database

Additionally "apk fix --directory-permissions" can be used to reset
all directory permissions to the database defaults.

Fixes #2966

This makes sure any conflicted packages will be removed first.
Useful if we know there are conflicting files, and want to avoid
adding potentially harmful replaces line. Add a test case for
this too.

Also if --purge is specified delete all uninstalled packages.
Fixes #2889

Allows one arch index files to refer to other arch packages. Mostly
useful with noarch packages, but could be used e.g. to ship build
with some of packages optimized for specific cpu generation and
share most packages with the standard build.

busybox trigger creates symlinks to itself. This helps user
to see where these come from.

It's real only if there's a package with actual dependency
(conflicts and install_if dependencies do not count).

allow packages in the cache's installed to be selected for installation
by the solver. add test case for the issue.

this happens e.g. after tmpfs boot when not all packages where
available: the dependency is in world, but not installed.

the dynamic applet registration never worked with PIE, and as
a temporary hack -nopie was added to default link flags in 2008.

this commit reworks the applet registration mechanism to something
that is compatible with PIE, and removes the hack. finally!

basically this makes packager's life simpler as there is no need
to list the subpkg names in replaces. this was also very error
prone and tedious job to do properly.

most notable in error report from 'del' applet

noticeable fixes upgrading of packages which get pulled in only
by install_if rule. this also simplifies the inheritance calculation
for packages, as well as the place where it is done for install_if
triggered packages.

'available' really means 'available in one or more configured
repository'. Cache is not a repository we track, so those are
only available for installation, but not available as preferred
to be installed from repository. fixes #2831.

fixes #2113

This implements a new protected path flag '!' to include always
matching entries in the backup mode (overlay). This is also turned
on for etc/apk to include everything there in overlay, because
the full list of repositories and signing keys need to be in
overlay - just getting them from a package is not enough during
bootstrap.

This reverts commit a99bedba.

Simply print the default arch and exit.
This is so scripts don't need to parse the output of -V.

Prevent the progressbar and status messages to mess up stdout.

Makes it more useful whith pipes.

stdout is the proper place for it. this also fixes the progress
bar in musl, which seems to not support using line buffering for
stderr.

http://ewontfix.com/11/