lei q --save: clobber config file on repeats

lei q --save: clobber config file on repeats

A user may wish to clobber/refine existing search parameters
by issuing "lei q --save" again.  Support that by overwriting
the lei.saved-search state file entirely.

We continue to preserve over.sqlite3 for deduplication purposes.

This way, we don't get something redundant like:

	[lei]
		q = term1
		q = term2
		q = term1
		q = term2
		q = term3

...whenever a user wants to refine their search.  Instead,
we'll just have:

	[lei]
		q = term1
		q = term2
		q = term3

On the second go.