Escape StringArray in ArrayCalculator

DataSet that contains String Data array prevents the calculator from working.
This fix just skips those types of arrays and lets the calculator do its work normally.

Change-Id: I66fb5ba72f488496634af017fd558f8e25a736d5
Merge topic 'fix-array-calculator' into master

64bce420 Escape StringArray in ArrayCalculator
fix TestEmptyInput for vtkDelimitedTextReader

Return early if this class is supposed to read from a file
and no file name has been set.

Change-Id: I84457c57893a851ee5917436cf50aa8a24ff8218
Fixed glsl compilation error on OS X 10.9

Renamed 'step' variable, which seems to conflict
with built-in step function, resulting in compilation
error on RogueResearch6 dashboard (OS X 10.9).

Change-Id: Ibee90a9ef3e86d9731103c01d04c23e154f70d07
Merge topic 'DelimitedTextReader_EmptyInput' into master

5e494022 fix TestEmptyInput for vtkDelimitedTextReader
Merge topic 'glsl-reserved' into master

1ce7c91d Fixed glsl compilation error on OS X 10.9