Tool to help find ABI breakages in package upgrades

ref #1484

- remove duplicate provides with so version 0
- exit with error if there are multiple provides with different versions

It is never and should never be used.

So far only openjdk6 needs it and uclibc cannot have it, so we make
it optional.

This will hopefully help detect depends problems early

and fall back to traditional so dependency tracing when not available

also sort the deps

This option will enable recursive search of shared-objects, which is
disable by default.

Skip .so files without version number in filename when soname has
version number.

This solves issue with libgcj/gcc-java who ships both libgcj_bc.so and
libgcj_bc.so.1.0.0 which both has soname libgcj_bc.so.1

So we actually scan those dirs

This is to avoid scan dlopen'ed plugins.

We scan any rpath set by any subpackage from same apkbuild. If it depends
on rpath to other package, developer will have to add that to ldpath.

This change means we have to move generation of .provides-so and .needs-so
til after all .rpaths are generated.

This changes the format of .provides-so file. We now add a column with
the version number

So it is not treated as a special 'virtual'
We use version number 0 for now.

some package (alpine-baselayout) needs to create /usr/local/bin etc.

POSIX only requires that filedesriptors 0-9 are available for shell
redirections.

was totally broke.