remove most of the font branching code

[#68292584]
use inherit to remove hardcoded font styles

[#68292584]
remove direct references to Lato

there are still 3 places in javascript files that seem to need the 
font-family defined. So these places are still using the
labConfig.fontface
[#68292584]
make sure lab/resources are copied to public
delete unused svg images
document fonts in Lab

[#68292584]
module for font css link tag in html templates

This way it can be used by the kramdown.erb as well
[#68292584]
remove Open Sans font references

[#68292584]
fix duplicate fontface definition

[#68292584]
remove open-sans local copy

[#68292584]