clearing assignments on deferred issues

Tim, please let the InferenceWeb folks know that we traced this to a firefox
problem.

This appears to be a Firefox problem. I'm not quite sure where in the call chain
we encounter this but as soon as the literal node drops below a (seemingly)
arbitrary length, it displays.

This seems to be related to Firefox's problems with long lines (4k limit) and
breaking up text nodes into adjacent nodes:
https://bugzilla.mozilla.org/show_bug.cgi?id=194231

This is being deferred as it is most likely either unable to be fixed or very
difficult to work around.

sheets will take a look, but we're not confident we can fix this for the next
release

yup; I reproduced the problem.

MAil from DebMcGuinesss <dlm@cs.stanford.edu>

... some triples with huge literal objects do not show-up . We think this may be 
a tabulator issue
In http://logos.cs.umbc.edu/iw/tami-scenario3-0720-en-tabulator-
label.rdf#f__g841, even if there is a triple asserting  (#f__g841, 
iwn3:hasN3string,  "blah...") in the RDF file, we cannot see the triple in 
tabled view.  However, when we reduce the length of the literal object,  the 
triple can be displayed in tabulator ( see  http://logos.cs.umbc.edu/iw/tami-
scenario3-0720-en-tabulator-label-short.rdf#f__g841).