Add registry navigation

[mattstermiller]

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Add read-only support for browsing the registry as a filesystem where registry keys are "folders" and values are "files". Add a "Registry" item in the root. Bookmarking should support registry paths. It should support searching for Key and Value names in the same way you can search for files and folders.

The Path should be fully compatible with regedit - copying a path out of regedit and pasting in Koffee should work and vice-versa.