Removed live reload script from each demo

Live reload script is injected by BEEFY
Using dist/css instead of custom CSS
Shortened the titles of the edit demo concepts
Added content to each node in the edit example
Added plugin to allow content editing in modals.

Allows editing of multiple existing content items.
Content node labels update when modified.
Added a method to return JSON for the graph object
Merge pull request #13 from knowledge-graph/JSON

Added a method to return JSON for the graph object
Merge branch 'master' into edit-modals
Added editing to the editing demo page

Removed editing from the example demo page
Updated knowledge-graph.js dist
Merge branch 'master' of https://github.com/knowledge-graph/knowledge-graph
Updata knoeledge-graph.js dist
Merge pull request #16 from knowledge-graph/demo-improvement

Demo improvement
Added editing to the editing example
Editing modals now appear if a node has no content
Added the abilit to add new content to concepts
New knowledge-graph.js dist file
Increased width of edit modal
Styled the edit-modals
Styled edit-modal buttons