* this package wraps the haiku_cross_devel package (i.e. it contains
that package in /develop/cross)
* the wrapper package is meant to be installed into the system
hierarchy, from where haikuporter will fetch the contained package
when needed
* Add new package haiku_loader.hpkg and move haiku_loader there. The
package is built without compression, so that the stage 1 boot loader
has a chance of loading it.
* Adjust the stage 1 boot loader to load the haiku_loader package and
relocate the boot loader code accordingly.
* build_haiku_image: Remove MIME DB creation code.
* Rename beos_mime source directory to mime_db.
* Add rules to build the MIME DB in the source directory's jamfile.
* Add MIME DB directory to haiku.hpkg in data/mime_db.
* Add optional packages Zlib and Zlib-devel.
* Simplify the build feature section for zlib and also extract the
source package.
* Replace all remaining references to the zlib instance in the tree and
remove it.
