Make sure animation speed isn't too slow

Previously, animations were set so the speed could be very slow.  Now,
it's at least one frame every two seconds.
almost got Jeff issue in
removed print statements
fixed Jeff bug when default and missing
reverting .vt files to default
Added test for this issue
Merge branch 'set-animation-speed-threshold-rebased'
Merge remote-tracking branch 'devel/issue_637_tweak_for_missings'
Use cdat packages
fixed issue #665 to avoid add_string multiple times.
fixed small bug in previous commit #666
Fix marker stretching.

The fitToViewport method applies an actor transform to map the geometery
into the window. This patch adds a transform filter on the glyph source to
correct the aspect ratio of the glyph source data.
Merge pull request #666 from arulalant/master

fixed issue #665 to avoid add_string multiple times.
got wmo pictures and size ok
Merge branch '553_stretched_markers'
good pix with not-strecthced markers, final tweaks to default sizes
Merge branch '553_stretched_markers'
Merge branch 'vtk_use_cdat_packages'
merged master back in
updated pictures to pass test, checked the new ones are still good