plugins: activePlugins() moved to PluginActivationService

Signed-off-by: Rafał Malinowski <rafal.przemyslaw.malinowski@gmail.com>
plugins: small improvement in PluginInfoReader

Signed-off-by: Rafał Malinowski <rafal.przemyslaw.malinowski@gmail.com>
plugins: add PluginInfoFinder class

Signed-off-by: Rafał Malinowski <rafal.przemyslaw.malinowski@gmail.com>
storage: move some methods from StorableObject to StoragePoint

Signed-off-by: Rafał Malinowski <rafal.przemyslaw.malinowski@gmail.com>
plugisn: add PluginInfoRepository::pluginNames() method

Signed-off-by: Rafał Malinowski <rafal.przemyslaw.malinowski@gmail.com>
plugins: changed semantics of PluginStateStorage

Signed-off-by: Rafał Malinowski <rafal.przemyslaw.malinowski@gmail.com>
plugins: importing plugin states from 09 moved to

Signed-off-by: Rafał Malinowski <rafal.przemyslaw.malinowski@gmail.com>
plugins: fix plugin activation code

Signed-off-by: Rafał Malinowski <rafal.przemyslaw.malinowski@gmail.com>