Build: Add architecture rule for libshared.a.

- As suggested by Ingo, add libshared.a to the architecture name map.
This allows it to be linked by its short name like other frequently
used libraries.
- Adjust all Jamfiles referencing the lib accordingly.

Use libstdc++, libsupc++ and libgcc from gcc_syslibs.

* Instead of faking libstdc++.so from libstdc++.a, use libstdc++.so
from the gcc_syslibs build feature for everything except x86_gcc2.
* Use libgcc_s.so from the gcc_syslibs build feature for everything but
x86_gcc2 (which still carries libgcc as part of libroot.so).
* Drop filtering of libgcc objects for libroot, as that is no longer
necessary since we're only using libgcc-as-single-object for libroot
with x86_gcc2, where the filtered object file doesn't exist. Should
the objects that used to be filtered cause any problems as part of
libgcc_s.so, we can always filter them as part of the gcc build.
* Use libsupc++.so from the gcc_syslibs build feature for everything but
x86_gcc2.
* Adjust all Jamfiles accordingly.
* Deactivate building of faked libstdc++.so for non-x86-gcc2. For
x86_gcc2, we still build libstdc++.so from the sources in the Haiku
source tree as part of the Haiku build .
* Put gcc_syslibs package onto the image, when needed.

More work towards hybrid support

* All packaging architecture dependent variables do now have a
respective suffix and are set up for each configured packaging
architecture, save for the kernel and boot loader variables, which
are still only set up for the primary architecture.
For convenience TARGET_PACKAGING_ARCH, TARGET_ARCH, TARGET_LIBSUPC++,
and TARGET_LIBSTDC++ are set to the respective values for the primary
packaging architecture by default.
* Introduce a set of MultiArch* rules to help with building targets for
multiple packaging architectures. Generally the respective targets are
(additionally) gristed with the packaging architecture. For libraries
the additional grist is usually omitted for the primary architecture
(e.g. libroot.so and <x86>libroot.so for x86_gcc2/x86 hybrid), so that
Jamfiles for targets built only for the primary architecture don't
need to be changed.
* Add multi-arch build support for all targets needed for the stage 1
cross devel package as well as for libbe (untested).

Fixed design issues in BPartitionParameterEditor.

* The user of an editor needed knowledge about the editor in order to make
use of it.
* Furthermore, the BPartitionParameterEditor exposed type specific
functionality that it shouldn't know anything about, either.
* We may now define a number of known parameters per editor type; right now
there is only "type" as it's needed by DriveSetup.
* Adapted all disk systems, and DriveSetup to the new API.
* Renamed CreateParamsPanel, and InitializeParamsPanel to *ParametersPanel
in DriveSetup.
* They now share a common base class AbstractParametersPanel.

NTFS: Added simple disk_system add-on for ntfs

Use libstdc++, libsupc++ and libgcc from gcc_syslibs.

* Instead of faking libstdc++.so from libstdc++.a, use libstdc++.so
from the gcc_syslibs build feature for everything except x86_gcc2.
* Use libgcc_s.so from the gcc_syslibs build feature for everything but
x86_gcc2 (which still carries libgcc as part of libroot.so).
* Drop filtering of libgcc objects for libroot, as that is no longer
necessary since we're only using libgcc-as-single-object for libroot
with x86_gcc2, where the filtered object file doesn't exist. Should
the objects that used to be filtered cause any problems as part of
libgcc_s.so, we can always filter them as part of the gcc build.
* Use libsupc++.so from the gcc_syslibs build feature for everything but
x86_gcc2.
* Adjust all Jamfiles accordingly.
* Deactivate building of faked libstdc++.so for non-x86-gcc2. For
x86_gcc2, we still build libstdc++.so from the sources in the Haiku
source tree as part of the Haiku build .
* Put gcc_syslibs package onto the image, when needed.

More work towards hybrid support

* All packaging architecture dependent variables do now have a
respective suffix and are set up for each configured packaging
architecture, save for the kernel and boot loader variables, which
are still only set up for the primary architecture.
For convenience TARGET_PACKAGING_ARCH, TARGET_ARCH, TARGET_LIBSUPC++,
and TARGET_LIBSTDC++ are set to the respective values for the primary
packaging architecture by default.
* Introduce a set of MultiArch* rules to help with building targets for
multiple packaging architectures. Generally the respective targets are
(additionally) gristed with the packaging architecture. For libraries
the additional grist is usually omitted for the primary architecture
(e.g. libroot.so and <x86>libroot.so for x86_gcc2/x86 hybrid), so that
Jamfiles for targets built only for the primary architecture don't
need to be changed.
* Add multi-arch build support for all targets needed for the stage 1
cross devel package as well as for libbe (untested).

Fixed design issues in BPartitionParameterEditor.

* The user of an editor needed knowledge about the editor in order to make
use of it.
* Furthermore, the BPartitionParameterEditor exposed type specific
functionality that it shouldn't know anything about, either.
* We may now define a number of known parameters per editor type; right now
there is only "type" as it's needed by DriveSetup.
* Adapted all disk systems, and DriveSetup to the new API.
* Renamed CreateParamsPanel, and InitializeParamsPanel to *ParametersPanel
in DriveSetup.
* They now share a common base class AbstractParametersPanel.

NTFS: Added simple disk_system add-on for ntfs