Fix some errors in interactive JSON metadata

[#43484231]
Rename components-metadata to interactive-metadata

[#43484231]
update sass, bourbon, and neat styling libraries

[#43606125]

Use neat for grid layout instead of plain box model
css

see: https://github.com/thoughtbot/neat/
removed src/sass/neat as submodule

[#43606125]

It is versioned and installed by using the Ruby Gem
distribution now.
Include neat grid-layout extension as generated files

[#43606125]

neat grid-layout is a grid layout extension to sass/bourbon.

Previously it was included in the project as a git submodule.

Now the versioning is handled in the Gemfile.

When the neat Ruby Gem is updated:

  cd src/sass
  rm -rf neat
  ../../bin/neat install
Gemfile: updates to guard and related gems
put src/sass/neat in *correct* directory!

[#43606125]
also fix layout for webgl-version of Energy2D

[#43606125]
cap task deploy::import_to_webapp

run "touch /var/www/app/server/tmp/restart.txt"
after loading new models.
server: fix elements in md2d model

also removed trailing whitespace!
remove more trailing whitespace from server/app
server: update code, run make before import

I'm finding that I am most often needing to update
the code before running the import:built_interactives
task. Running a plain 'make' command is usually much
faster than what the cap task deploy:update does which
is 'make public'. Running make public actually deletes
and rebuilds the public dir -- basically all the generated
resources.
change name of cap task to deploy:built_interactives

To matth the rake task name ... much easier to remember
if they are the same.
server: added debugger gem to dev section of Gemfile


This enables starting up the rails server in debug mode:

  rails s -u
server: move /md2d_models => /models/md2ds
cap task: import interactives RAILS_ENV=production!
server: Gemfile update: sass, bourbon, neat, guard

matches versions used in lab proper
server: sample for config/settings.yml

Allows hostname configuration per server.
modify presenters/base to return correct hostname
server: more complete md2d model and presenter

better matching of actual md2d model ...