PackageWriterImpl::_AttributeRemoved(): Update string cache

When removing a string attribute, decrement the referenced string's
usage count in the string cache. This fixes the potentially incorrect
usage counts in update mode. Not a serious problem, but it could lead
to only singly (or no longer) used strings to be written to the string
subsection instead of encoding them inline and thus to slightly greater
file sizes.

Refactoring step towards implementation of RepositoryWriter:
* pulled commonly useful parts out of PackageWriterImpl into
WriterImplBase
* moved CachedStringTable and related methods into a separate class,
StringCache, in order to support having more than one string cache
per package file
* made package attribute section use a string cache, too, as that's
going to be very useful for repositories
* instead of writing package attributes directly, we now collect
corresponding PackageAttributes and write those later
* adjusted package reader accordingly


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@40376 a95241bf-73f2-0310-859d-f6bbb57e9c96

Refactored hpkg implementation to provide some separation between
public and private API (still far from ideal, but a start):
* moved several HPKG-classes into the public namespace BPackageKit::HPKG
* added fImpl-wrappers around PackageReader and PackageWriter to hide
most of the gory details
* adjusted 'package'-binary and packagefs accordingly


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@40320 a95241bf-73f2-0310-859d-f6bbb57e9c96

More work on package kit:
* added class BPackageInfo, which contains packaging attributes of
a package (the values relevant for package management)
* implemented parser (mostly) for reading a BPackageInfo from a config
file (.PackageInfo) in order to pass them on to the PackageWriter
when creating a package
* pulled hpkg-related stuff from bin/package into the package kit
* adjusted packagefs-Volume to skip .PackageInfo files when populating
the mountpoint, as those files shouldn't appear as part of an
activated package


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@40301 a95241bf-73f2-0310-859d-f6bbb57e9c96

PackageWriterImpl::_AttributeRemoved(): Update string cache

When removing a string attribute, decrement the referenced string's
usage count in the string cache. This fixes the potentially incorrect
usage counts in update mode. Not a serious problem, but it could lead
to only singly (or no longer) used strings to be written to the string
subsection instead of encoding them inline and thus to slightly greater
file sizes.

Refactoring step towards implementation of RepositoryWriter:
* pulled commonly useful parts out of PackageWriterImpl into
WriterImplBase
* moved CachedStringTable and related methods into a separate class,
StringCache, in order to support having more than one string cache
per package file
* made package attribute section use a string cache, too, as that's
going to be very useful for repositories
* instead of writing package attributes directly, we now collect
corresponding PackageAttributes and write those later
* adjusted package reader accordingly


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@40376 a95241bf-73f2-0310-859d-f6bbb57e9c96

Refactored hpkg implementation to provide some separation between
public and private API (still far from ideal, but a start):
* moved several HPKG-classes into the public namespace BPackageKit::HPKG
* added fImpl-wrappers around PackageReader and PackageWriter to hide
most of the gory details
* adjusted 'package'-binary and packagefs accordingly


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@40320 a95241bf-73f2-0310-859d-f6bbb57e9c96

More work on package kit:
* added class BPackageInfo, which contains packaging attributes of
a package (the values relevant for package management)
* implemented parser (mostly) for reading a BPackageInfo from a config
file (.PackageInfo) in order to pass them on to the PackageWriter
when creating a package
* pulled hpkg-related stuff from bin/package into the package kit
* adjusted packagefs-Volume to skip .PackageInfo files when populating
the mountpoint, as those files shouldn't appear as part of an
activated package


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@40301 a95241bf-73f2-0310-859d-f6bbb57e9c96