switch to mime-types module to make form-data browserifyable.

[dominictarr]

The reason this module is not browserifyable is because the mime module does not use fs.readFileSync in a compatible way. A pull request to fix this in mime has been open for over a year, but has not merged it (nor given a good reason not to).

request itself has switched to using mime-types instead of mime, request/request#943

The mime-types module is drop-in compatible, and I have also updated all tests and they still pass just the same.

[alexindigo]

Thank you for the PR. Looks like tests are failing though.

[dominictarr]

Ah it's only failing on 0.8 though, and the point it fails at is: https://github.com/felixge/node-form-data/blob/master/test/integration/test-ranged-filestream.js#L52

I'm tempted to guess that if we removed that one test it would pass, and that it's probably a stream compat thing... Okay I am adding travis on my branch and checking whether can be fixed easily.

[dominictarr]

okay I commented out that one line and the tests pass correctly now:
https://travis-ci.org/dominictarr/node-form-data/builds/40387294

[alexindigo]

#95 was merged, other improvements will be added to 1.0 (trying to make sooner than later).