quvi-dump: Postpone print after querying metainfo
With the (unbuffered) 'enum' of core.print-format, the program will:
1) print the media properties
2) query the metainfo properties for the media stream
3) print the media stream properties
This causes a notable pause in the output when the program stops to
query the metadata (when applicable).
This commit changes quvi-dump so that the (unbuffered) output is printed
*after* the metainfo has been retrieved. This changes nothing for the
buffering filters (rfc2483, json, xml).
Signed-off-by: Toni Gundogdu <legatvs@gmail.com>