ready to start testing this

modified:   lib/trigger_vds_impute_trucks.js

rewrote to use the more limited queue from Bostock.  Not using waterfall
model as with async library, but the callback cascade isn't too
dreadful.

The one issue is I like assigning callbacks when each item is completed
to see what is up, but then again, I have console.log statements in the
call R code for when each job is started, so there you go.
ready to start testing this

modified:   lib/trigger_vds_impute_trucks.js

rewrote to use the more limited queue from Bostock.  Not using waterfall
model as with async library, but the callback cascade isn't too
dreadful.

The one issue is I like assigning callbacks when each item is completed
to see what is up, but then again, I have console.log statements in the
call R code for when each job is started, so there you go.

modified:   lib/trigger_R_job.js
added a little message mechanism too