* filter backup details by flags
`backup details` should have its output filtered by the flags provided by
the user. In addition, the selector's FilterDetails should maintain
information (esp service info) about the entries, rather than slicing them
down to only the path reference.
* add output formatting control to cli
Adds the capacity for the CLI to output either a
text table or a json blob to the terminal. Table is
the default behavior, json is toggled with the --json
flag.