openssl BIO does not close the fd unless we explicitly tell it to
do so.

So it'll be easier to rebuild affected packages. Fixes #349.

Doing "apk add file.apk" adds a versioned dependency to allow
downgrading, and sticky version. Most often this is to install
single packages from newer repository. So it would make sense
to reset them to non-versioned if doing:

 apk upgrade -a

fixes #346

Check that package name has packages associated with it before
dereferencing the pointer. Fixes #345.

they do not have any package associated. this is indicated by
package with zero installed_size.

even if we have only one package as candidate, we need to check
it's availability. otherwise we can endup with bad changeset
referring to unavailable package.

we do not create mirror repositories from other valid repositories,
not from what was installed locally.

wget:ing local files results in error and is useless.

add the missing variable.

otherwise regeneration of non-repository index might go wrong or we
might delete too many files from cache when doing 'cache clean'.

prints like:
(1/12) Installing...
(2/12) Installing...
etc...

This makes things a little bit nicer when installing from network with
slow lines.

We want see all packages that fails to install and not only the first

got broke few commits ago when apk_pkg_installed() call was
moved to happen after the package name has been read.

When pressing only <enter> on the question "..continue [Y/n]?" then
lets take that as a "yes"

this is now mandatory after the overlay fixes. otherwise the
package will not get listed as installed.

turns out the logic does not work with overlays as expected due
to busybox symlinks being unmanaged. remove the useless option.

appears this is possible, so support it.

lookup proper directory instance as the tar output might not be
linear.

get list of overlay files from stdin, so those do not get overwritten.

less syscalls.

do not overwrite target if we have --never-overwrite and target exists.

ref #197

otherwise we always extract the file as .apk-new and the database
side just overwrites.

add cvs, svn, git and mercurial tags for creating snapshot
packages.

even more corner cases found which were broke. now all tests
should pass.

so i don't get to break version compares again.

to never ever overwrite a while in the filesystem the user knows
about. it gives the impression of extraction succeeding even though
nothing was done. this is inteded to be used only for bootstrapping
with overlay.

-t 1.3-r0 1.3.1-r0 was broke

the old code treated a symlink to directory as file; it tried
to calculate regular has of it. fix this by: 1) using no follow
on migration and pruning stats, and 2) the helper function to
check if it's point to directory and not calculate hash in that
case. fixes #188.

got broke in 0b9bfa8d which
fixed another corner case. hopefully it's good now. fixes #191.

if the dependencies are empty with only trailing new line, the
parsing was incorrect. fix the new line check.