Add drawing of workflow DAG

[mrwalker]

From @abeppu, adds drawing of workflow DAG in d3. His comment on the initial commit:

this may look weird in d3, but I think the nice benefit is that we can (w/ a little work) do things like color according to status, have scroll-over info, etc.

[jgoulah]

example:

[rathboma]

Sorry it took so long for me to look at this.

Can we make the graph div hidden by default and add a 'reveal' button. Just thinking of the case where a workflow is pretty large.

Also, could you squish the commits into a single commit? Then I'll happily merge.

[jgoulah]

yup, there is a big part of me that wants tabs on this page, where the job definition, and then graphs are both on separate tabs. both of those can get pretty big for us. maybe out of scope for this change set but any thoughts on that?

[rathboma]

I'm definitely not opposed to tabs, I do like to find things on the page though, so wouldn't want to go crazy with the tabs.

Also agree that this is probably outside the scope of this changeset.

[jgoulah]

redid this pull request here since you wanted everything squashed:

#6

[jgoulah]

this should be closed, in favor of pull #7