Added build image.
Added some more tests for knowledge graph creation

Tests for knowledge graph creation and adding concepts
These tests are currently broken as we aren't returning the knowledge graph
Added unit test for basic plugin API.
Fixed test code

Added beforeEach calls instead of assuming things run in order
Fixed knowledgeGraph.create() called with no param

knowledgeGraph.create() no longer breaks if called with no arguments
Added ids of nodes to svg elements
Made plugin API tests pass.
Small tweaks.
Merge branch 'plugins' into interactive

Conflicts:
	src/knowledge-graph.js
Fixed case when no graph object.
Each knowledge graph is a new object.
Un-nest tests.
Split editing into a plugin.
Added a link plugin to link concepts to content

Currently uses a concept's 'link' attribute
Fixed permissions on git hooks

Added execution permissions for the git pre-commit script
Added a script for building distributions

Script can build full version and version without D3
Added watch commands

Files will be watched during tests and during beefy hosting
Changed builder from shell script to JavaScript

Allows us to take advantage of npm varaibles etc
Distribution files are no longer tracked by git

Run "npm run git-setup" to ignore tracked distribution files
Allow plugins to be registered and referred to by name.