Update query to get scan data for the Scans per site chart.

The new query groups by session ID so that one scan session is counted as a scan. Previously the query was just counting the number of files in the files table.
Update new and pending scan query.

The old query was not grouping files by session, as is done in the imaging browser.
Update title of scan chart to match the changed query.
Update scan queries to use count(distinct s.id)

for bin in `cat $1`
do
  echo "Making tables for BIN $bin"
    #time ./pangen sha1 $bin 4 500 2000000 $bin
    time ./pangen sha1 $bin 4 400 5000000 $bin
    #>> "$1.log.txt"
    filename="sha1_"4"_500x2000000_$bin.rt"
    #./rtsort $filename
done
Merge pull request #750 from taracampbell/dashboard_scan_queries

Dashboard scan queries