add jsTree javascript library.
include new library.
Merge branch 'master' into topic/jstree
a embryonic version of a tree-based trial page.
add AJAX code for generating pages for trials.
check for nullness.
double click opens trial page, download link activates only on leaf nodes... :-)
remove alerts.
implement rudimentary multiple download feature.
add a csv download.
tweak position of buttons.
make downloads with complete trial info possible.
double click on node will link to the trial page.
Merge branch 'topic/jstree' into topic/trial_location
also retrieve the rep for each measurement.