trivial: Fix build warning when using gzFile
Do not rely on g_slice_new() being zeroed

This fixes a crash on some systems.
Do not crash if a package does not have a URL set
trivial: don't show a warning on the console for an unknown transaction phase
Ensure all errors are reported in the zif command line tool

Correctly set the error return value when non-boolean values are returned.
trivial: Use g_error_matches() in two more places
If the ZifStore gets disabled don't keep trying to use it in ZifStoreArray
Do not return primary metadata when the ZifStore is not enabled
Don't allow a store to be added to a ZifStoreArray more than once
Add zif_transaction_get_update() for pre-resolve checks
Filter the *-release packages before finding 'releasever_pkg'

This reduces the startup time of zif by about 760ms.
Store the file checksum in the xattr to speed up checking metadata at startup

This reduces the startup time of zif by about 700ms.
Only read the metadata files from disk if we need to check the contents
trivial: Remove an unreachable code path
trivial: Remove some unused variables found using coverity
trivial: Remove some dead code spotted by coverity
Turn off header validation when loading the rpmdb

This typically speeds up zif startup by 1400ms.
Ignore any fractional part of the timestamp when parsing repomd.xml
Don't reset the parent state when getting package requires
Don't use the deprecated sysconfig files that have been removed in F18