Support uncompressed bundle

[PengZheng]

Now that #476 splits the cache and storage, the most straightforward way of supporting efficient sharing of bundles between multiple Celix instances is to add support for uncompressed bundle. This way, each framework instance has its own bundle cache like before, but for shared bundles, we extract them to someplace outside of bundle cache (maybe make them read-only), and then make symbolic links within the bundle cache to uncompressed shared bundles.

For containered/sandboxed APPs, we can mount folder containing uncompressed bundles read-only into the container/sandbox, and include the mount point into the bundle path, so that the framework within the container/sandbox can find them.

Originally posted by @PengZheng in #509 (comment)

[pnoltes]

Yes, this has become more straightforward.

What about adding support in the install_celix_bundle cmake function to install bundles zip uncompressed (as dir) instead of zip. Maybe with an option INSTALL_AS_DIR.

This can also be used to prep a bundles directory structure as mount entry, but I think this can also function to supported bundles installed as dir in `/use/share//bundles/a_bundle_dir