Notify user of held package transactions

[kallisti5]

After running pkgman update, additional package transactions are held until the next reboot. This isn't super obvious and means any additional package changes aren't reflected on the running system.

Example:

• llvm7_clang installed
• system updated
• llvm7_clang uninstalled
• clang binary still present

syslog

KERN: package_daemon [309851714298:   648] CommitTransactionHandler::_ChangePackageActivation(): activating 6, deactivating 6 packages
KERN: package_daemon [309852214679:   648] Volume::_PackagesEntryRemoved("grep-3.1-1-x86_64.hpkg")
KERN: package_daemon [309852220303:   648] KERN: Volume::_PackagesEntryRemoved("haiku-r1~beta1_hrev52678-1-x86_64.hpkg")
KERN: package_daemon [309852226951:   648] Volume::_PackagesEntryRemoved("webpositive-r1~beta1_hrev52678-1-x86_64.hpkg")
KERN: package_daemon [309852233977:   648] KERN: Volume::_PackagesEntryRemoved("makefile_engine-r1~beta1_hrev52678-1-any.hpkg")
KERN: package_daemon [309852241066:   648] Volume::_PackagesEntryRemoved("haiku_devel-r1~beta1_hrev52678-1-x86_64.hpkg")
KERN: package_daemon [309852248093:   648] KERN: Volume::_PackagesEntryRemoved("haiku_loader-r1~beta1_hrev52678-1-x86_64.hpkg")
KERN: package_daemon [309852255181:   648] Volume::_PackagesEntryCreated("haiku-r1~beta1_hrev52692-1-x86_64.hpkg")
KERN: package_daemon [309852261844:   648] KERN: Volume::_PackagesEntryCreated("makefile_engine-r1~beta1_hrev52692-1-any.hpkg")
KERN: package_daemon [309852268931:   648] KERN: Volume::_PackagesEntryCreated("haiku_loader-r1~beta1_hrev52692-1-x86_64.hpkg")
KERN: package_daemon [309852276019:   648] Volume::_PackagesEntryCreated("webpositive-r1~beta1_hrev52692-1-x86_64.hpkg")
KERN: package_daemon [309852283046:   648] KERN: Volume::_PackagesEntryCreated("haiku_devel-r1~beta1_hrev52692-1-x86_64.hpkg")
KERN: package_daemon [309852290073:   648] KERN: Volume::_PackagesEntryCreated("grep-3.3-1-x86_64.hpkg")
KERN: package_daemon [314147262605:   648] CommitTransactionHandler::_ChangePackageActivation(): activating 0, deactivating 1 packages
KERN: package_daemon [314147762849:   648] Volume::_PackagesEntryRemoved("llvm7_clang-7.0.1-1-x86_64.hpkg")
KERN: package_daemon [314175309312:   648] CommitTransactionHandler::_ChangePackageActivation(): activating 0, deactivating 1 packages
KERN: package_daemon [314175809538:   648] Volume::_PackagesEntryRemoved("llvm7-7.0.1-1-x86_64.hpkg")

All of the messages after the update report a success, but don't mention the changes are being held.

Ideally, pkgman should report that "Warning: A pending system update has occurred, these changes will not be available until after the next reboot" or something similar.

We also need to figure out how to present the user with this info when the change occurs via the UI.

[korli]

The package kit part was added in hrev52999.

[waddlesplash]

SoftwareUpdater now displays this, so it's just pkgman that now needs to.

[waddlesplash]

HaikuDepot and pkgman now do so as of hrev53176.

[nielx]

Assign tickets with status=closed and resolution=fixed within the R1/beta2 development window to the R1/beta2 Milestone