Jsop

New format for the JSON output of the `export` command line option.

This allows using `diff`, and makes any diff-based backup more efficient.

Added read-only access mode, for better use of locking mechanisms.

Extended API: Now virtually all dictionary and list operations are supported.

This makes transition to JSOP of existing JSON-based applications even easier than before.

Fix for a bug that affected garbage collection.

First release.