d3 based diagram UI component

[stevebuik]

a d3 force directed graph where the nodes are html tables could replace the diagram with a lot more interactive features

• drag/drop repositioning of the entities. in d3 it's possible to lock a node in place so any node that is dropped can lock in place, the others will adjust automatically.
• the edges in the chart will be lines but it should be possible to calculate the two right angled lines horizontal/vertical lines to make a better connector with an arrow on the end
• when groups are added to graphviz diagrams, d3 supports auto-calculated grouping containers so these be be used for groups https://bl.ocks.org/bumbeishvili/f027f1b6664d048e894d19e54feeed42
• entities can be drag/dropped from one group to another
• better visualisation/animation of entities that are part of a SOQL query

any of these features needing data persisted can add a section to the JSON schema / persisted document shape

it can be another tab next to download, giving the user choice.

[stevebuik]

in UMD format so it is consumed in the same way as the pure.js module