Cosmetic changes to whitespace

Make it easier to edit in Vim
Fix "rhizome hash file" command for nil files

Now returns an empty result for zero-length file or zero-length file name

Test framework only invokes on non-zero-length files
Improve comments on Rhizome db functions
Make some Rhizome db functions static
Improve Rhizome debugging

Log the integer result of an int64 query
Refactor rhizome_cleanup()

Compute time horizons once only, not once per query

Factor query that deletes orphan FILEBLOBS rows into its own function
Fix duplicate payload logic

rhizome_finish_write() was treating a duplicate file hash as an error,
instead of dealing with it sensibly
Rename 'rhizomeops' test case

AddDuplicate -> AddDeDuplicate
Improve Rhizome test functions

Options to allow manifest name to be given explicitly to override the
conventional "<filename>.manifest"
Add "rhizome add file" --force-new option

Overrides the default behaviour of de-duplicating added manifests

New 'rhizomeops' test case: AddForceDuplicate