Add nomnoml rendering feature

[korroz]

Makes StackEdit capable of rendering nomnoml code within fences, much like the other uml features. Fixes issue #645.

This is how it looks in action:

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I kept the commit clean, but I'm not entirely sure that's what I should do. Or should I commit the minified build and the messy updates following gulp bower-requirejs as well (I think RequireJS got upgraded as well)?

Let me know how you want it and I'll fix it.

[benweet]

Hi @korroz
The commit looks good. Just 1 thing, I'm not confortable including lodash and underscore in the same project. I think nomnoml was using underscore before your Librarify task. Is there any strong dependency on lodash or could it work with underscore only?

[benweet]

By the way, SVG rendering would be great (portability, support for CSS theming). I had a quick look at skanaar/nomnoml#15, but it looks like @ctzurcanu didn't make his pull request. Is there any blocking issue?

[ctzurcanu]

@benweet Yes: I was talking with @korroz about other ways to render svg besides canvas2svg lib and there are 1-2 nontrivial bugs that are related to nomnoml not providing sufficient data to an outside renderer. Had not have the chance to check if nomnoml library solves this.

[korroz]

@benweet yeah that bothered me as well actually. Especially since there is no specific reason anymore. In my work I made an attempt to upgrade dagre as you can read in the commit message of 16c7e400. But later I had to revert the upgrade for reasons mentioned in the commit message of 968dfd00.

The bottom line is that nomnoml is compatible with either lodash or underscore. I'll take a look at solving this dependency.

Regarding SVG rendering, this should probably be viewed as a medium term milestone for now, unless there is a pull request that satisfies @skanaar. We're discussing it already.

The current state of nomnoml (in StackEdit) is still made portable by rendering an <img> instead of leaving it as a <canvas>. This means that Export as HTML and similar functions work as expected in StackEdit. Talking about theming, that is injected as a preset directive for now. I was going to see if the theme palette could be accessed programatically but I'm still new to the StackEdit code base.

Lastly I'd just like to say that I also, in the end, think SVG is a better match for nomnoml. In fact that was one of the first things I discussed with @skanaar.

[jakupmichaelsen]

When will this feature be integrated into StakEdit, or what do I need to get it to work?