Refactored Plugin, MeshCat, GraffSDK, and Julia 1.0 Release
This release switches to MeshCat and Julia 1.0 as standard, as well as allowing standardized plugin chains for easier expansion of features. Plugins can reside in any scope and fed to main visualize
via the plugins
function callback vector. This release also uses the new GraffSDK web access. Please see Milestones for more details.