Add "Menlo" to monospace font list.

[isoos]

"Source Code Pro" is not installed on Mac, and the default monospace font makes the table's markdown-formatted fixed table's header line stick out. (Screenshots in this issue thread: dart-lang/pub-dev#1125 (comment)).

Closes #1644

[jcollins-g]

Looks good, but use grind update-test-package-docs to fix the travis failure.

[isoos]

I've run pub run grinder grind update-test-package-docs, updated the PR, but I'm not sure why the CI is still failing.

[jcollins-g]

That doesn't look like it is your break. Something is wrong with sdk doc generation (or, we're correct and verifying the wrong thing if they've changed the SDK somehow). I'll look into it.

[jcollins-g]

#1650 will alleviate the travis failure.

[isoos]

Rebased, PTAL.

[jcollins-g]

lgtm

[jcollins-g]

i may land more changes. assuming the tests are green go ahead and land after rebasing

[isoos]

@jcollins-g: I don't have merge rights...

[jcollins-g]

Actually, I'll just land this myself right now; I'm hoping to gear up for another release sometime today and want this to make it.

[jcollins-g]

@isoos Oh. Not clear to me how to tell on that sort of thing. Merging :-)

[isoos]

Thanks! :)