Fix IntegrateAttributes so it works when node 0 has no data.

This may happen after a Threshold. We find out the minimum node that
has data and send it to node 0.

Change-Id: Id0dfa4b02b0b4a1cb484525e0116fd8be9fd914b
Add documentation to 'Interpolate Scalars Before Mapping' check box.

Change-Id: I37d96061fcda8498707972ce9e243860b539bbbe
BUG #14295: Make it easier to clear text in search box.

Make it easier to know how to clear text in search box by adding text that
points to using Esc key to clear the text.

Change-Id: I057ea3d0e05fd64deb97a177ebee2d850f45db72
Merge topic '14295_search_text'

73678b9 BUG #14295: Make it easier to clear text in search box.
Merge topic '14342-integrate-empty-servers'

9f9d72e Fix IntegrateAttributes so it works when node 0 has no data.
Merge topic '14350-opacity-interpolate-scalars'

f3ab2b0 Add documentation to 'Interpolate Scalars Before Mapping' check box.