Reverse axes first pass
new svg container bric, a real HtmlBric
switch some demo files to new SvgContainer
Change BricLayer to build new svg container not old prototype
The xAxisIsReversed_/yAxisIsReversed_ properties are now set to null for ordinal axes.  Added unit tests.
Merge branch 'master' into 674_reverse_axes
make unit tests use new SvgContainer

had to add a dummy do nothing erase method to several proto brix so the tests would pass.

- Image
- CaptionedImage
- Carousel
- ProtoBarChart
- ProtoLineGraph
- Sketch
some changes to EnergyCompareNewLineGraph.html

overall this example is too complicated to start w/ for demonstrating previous functionality. A new mortar which I have termed ToggleSelection is needed, and there will be less dataswapping needed I think.
fix SvgContainer config in tests/integration/pafjson files
Updating config
one more var rename in the linegraph unit tests
fix AgeStructureCountries, AgeSim

which entailed fixes to the barchart bric and proto-agestructure mortar as well updating their config to replace proto brix.
The contents of this file make no sense, deleting.
update AgeStructureCountries.html in demo/Neff to use new brix
update template_custom_mortar which uses the waveform mortar.
Update two templates to use xhtml and new svg container
new svg container
Moved to new SVG container config
code review changes for reverse axis - all minor
Completely reconstituted this bad boy which was about a year out of date.  Uses New SVG logic, and has an image carousel and linked callouts.  Should devise a way to use text links in the event process based on their target anchor or something.