add 10m resolution data (fixes #6)

[silky]

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[etpinard]

Great. I'm glad this worked out.

Now, can you require those new _10m files in the package index.js and make the [testshttps://github.com/etpinard/sane-topojson/blob/master/test/test.js) pass?

[silky]

ci failed because firefox crashed.

is that a known problem? or is it because the 10m data is too much for it to handle?

-- edit: it crashes on my computer too.

oh well, i guess we forget this idea then; i leave it to you to reject this PR unless you can see a way to save it.