added more documentation block at top of calc_aadt && return outliers

Also am now returning outliers as part of the return object
added inclusion of outliers in response, plus a test to make sure
test to make sure that freeways w/o outliers do not have object

In the response from freeways without outlier records, you can test
aadt.outlier should not be defined

if(task.aadt['freeway'].outlier !== undefined){
 then you have outliers in your data set.
}
minor edits, getting rid of debug statements