[entropy.db] add listAllInjectedPackageIds
[entropy.qa] _get_missing_rdepends: if package does not need any library, return straight away
[entropy.qa] rewrite _get_missing_rdepends, now _get_missing_libraries

This commit dramatically improves the speed of _get_missing_libraries,
by using provided_libs metadata instead of content, removing any live
system dependencies (collect_linker_paths()), and improving method
readability.
[entropy.db] add listAllSystemPackageIds() method
[entropy.qa] _get_missing_libraries: cache the list of system packages
[entropy.qa] remove unwanted output message from test_missing_dependencies.

The message heavily depends on the context in where test_missing_dependencies
is executed.
[entropy.server] add QA test for library linking of injected packages

This test must pass before being able to push new packages and it ensures
that injected packages are kept consistent.
[eit.commands.test] if "eit test deps" reports missing deps, return != 0
[entropy.qa] split test_missing_dependencies, move ldd-based scan to warn_missing_dependencies
[entropy.qa] improve output of test_missing_dependencies()
[entropy.qa] fix typo in test_missing_dependencies()
[entropy.qa] test_missing_dependencies: cosmetic changes to the generated output
[entropy.server] tweak output of injected_library_dependencies_test
[entropy.server] drained_dependencies_test: improve readability of the output
[entropy.server] fix undefined reference in drained_dependencies_test
[entropy.qa] test_missing_dependencies: only consider direct dependencies

Any missing ELF level dependency should be always satisfied by direct
dependencies.
[entropy.qa] warn_missing_dependencies: stop using get_deep_dependency_list, too slow and unwanted
Merge remote-tracking branch 'upstream/master'