Properly handle subslots in ::unavailable
master is now 0.81
Introduce SlotUnknownRewrittenRequirement
Parse/generate SlotUnknownRewrittenRequirement in Gentoo EAPIs
Trim whitespace before deciding whether key values are empty
Fix test fails
Preparation for 0.82.0
master is 0.83
stripper: refactor the action description strings

The action description strings are used by the subclasses of the stripper.
Rather than duplicating them, move them into the base class.

Reorder the functions to match ordering and annotate virtual and overrides.
stripper: add support to compress DWARF sections

This adds a new dwarf_compress build option to use dwz to compress the DWARF
information in executables and libraries.  Use of this functionality requires
the dwz package to be installed and available in the default path.  Enabling
this during builds can reduce the size of the *compressed* symbols by an
additional ~10-25%.
doc: update documentation for new dwarf_compress bo
ebuild: reorder and uniformise PATH

Make the search PATH order prefer the secondary hierarchy (/usr) as it is the
primary point for user binaries.  Still permit falling back to the primary
binary (user and system) directories in the case an executable is not found in
the user supplied path, nor the secondary hierarchy.

Make the PATH setup uniform across normal and binary ebuilds as well as during
VDB updates.
ebuild: be more cautious when modifying the path

Be more cautious when prepending to the path to avoid an empty component in the
caes that the PATH is empty.
build: de-duplicate tidyup hooks
autogen.bash: Split non-autotools logic

This allows to run the usual autotools logic on the package manager side
Allow EAPI 5 subslots in user package dep specs
stripper: dwarf_compress is not available for pbins

The strip phase is not executed for pbins.  dwarf_compress is an option to
control the emission of debug data, which is generated by the strip phase.
Simply restrict the dwarf_compress option in the case that we are involved
in a pbin resolution.
build: Fix compilation with gcc 4.7
Preparation for 1.0.0
Fix Python with GCC 4.7

Fixes: ticket:1259