import of sets of heterogeneous flatfiles from arbitrary sources

Sometimes it is necessary to import several flatfiles at once. E.g, if a web server provides an alignment file, a tree file, several annotation files and several structure files, all of which would be destined for one alignment view (plus any additional tree viewers needed).

Operations like the above are currently implemented in an ad-hoc fashion according to need at a particular point in time. A simple mechanism is needed to programmatically import sets of (possibly already identified) flatfiles, which will facilitate simpler web service and file import code in future versions.