Copy over node buffer tests

[jessetane]

These patches pull in node's buffer tests and make the changes required to pass them.

This includes a proper fix for #48 /cc @trollixx.

[feross]

This is an incredible PR! You are awesome @jessetane!

Will release 3.0.0 tonight, because this PR contains many breaking changes (for the better):

• toString('ascii') and slice('ascii') work correctly (strip off high order bits)
• correct exception types thrown (RangeError instead of TypeError in many places)
• do not encode partial code units to utf16
• do not encode partial or invalid code points to utf8
• copy() returns length

[feross]

I just added you as a github collaborator! Please follow the OPEN Open Source guidelines :) And thanks for being awesome!

[jessetane]

Very cool, glad to be able to help out!

It looks like the tests may be taking too long after all? I can't immediately tell:

https://s3.amazonaws.com/archive.travis-ci.org/jobs/44993014/log.txt

If need be, the node tests can be downloaded without transforming to use tape and they will run almost instantly with assert - tape output would be sacrificed, and a single failed test would crash the whole process, but they would be fast...

[feross]

Looks like it. I don't think tap output is super important for the node tests, and they do cause a lot of traffic from the browsers (sauce labs) back to the test harness (travis) which increases the flakiness of the tests.

Were you able to run the zuul tests locally? You can make an open source sauce labs account and follow the instructions here: https://github.com/defunctzombie/zuul/wiki/Cloud-testing

[feross]

This might be hard to do as a transform, but leaving the tight loops as asserts and just inserting a single t.pass('xxxx test passed') message at the end would be a good balance between informational test output and speed.

[jessetane]

I tried running the tests in local browsers but not at sauce, lemme try that real quick.

[feross]

Okay, 3.0.0 is released now.

[jessetane]

w00t!

[feross]

@jessetane I just merged your base64-js PR (beatgammit/base64-js#10). Could you send a PR to buffer to remove the special handling you added here?