SciDAVis - Improvements SciDAVis Copy

In particular, DataCurve::tableRow() was broken for DataTime values as well as
for columns with non-unique values. Screen picker and the tracker text of
data picker have been modified to use the same output format as the
bottom/left scales (currently hard-wired, switching to top/right would require
a user interface to be made up). The status bar output of data picker uses the
same format as the underlying columns of the selected curve.