/archives returns all entries rather than 0
/archives returns all entries rather than 0

On /archives, 0 entries were returned because the filter is not
populated with a date string, so no entries matched.  The filter in this
case is populated with the request type.  To return all entries on
/archives, check if the filter matches a date string.  If the filter
matches a date string, select entries with the filter, otherwise select
all entries.

This patch considers the filter to match a date string if its first four
characters are digits.

nviarnes/custom_toto,stevepaulo/toto,mattvanhorn/toto,mclaughj/toto-tags,mattvanhorn/toto,wulftone/toto,stevepaulo/toto,wulftone/toto,rschmukler/Glinda,sbsurf/toto,D-Roch/Blog-toto,blanchma/toto-extended,nviarnes/customized_toto,ixti/toto,cloudhead/toto