$ git log --author="Justin" --pretty=tformat: --numstat --no-merges --since='2015-12-03' --until='2015-12-10' |grep -v sdks|awk '{s+=$1; s2+=$2} END {print "add=" s;  print "del=" s2}'
add=2373
del=841

$ git log --author="Justin" --pretty=tformat: --numstat --no-merges --since='2015-12-10' --until='2015-12-17' |grep -v sdks|awk '{s+=$1; s2+=$2} END {print "add=" s;  print "del=" s2}'
add=718
del=457

$ git log --author="Justin" --pretty=tformat: --numstat --no-merges --since='2015-12-17' | grep -v sdks|awk '{s+=$1; s2+=$2} END {print "add=" s;  print "del=" s2}'
add=1384
del=708