Make this package compatible with latest meteor/meteorite

Hi, I'm just making this pull request just to make some of your packages compatible with the latest meteor/ite.
Had some issues trying to make them work and came up with some fixes.

Hope you can pull and merge this if you consider so.
Thanks in advance!

Commit comments:
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Updated package.js to add dependencies for the crytpo-base and crypto-md5 packages.

Removed cripto-js folder aa libraries inside are already placed as dependencies in package.js.
Changed how the Belt namespace is defined in md5_common.js