Test cases and SDK update

[songz]

1. Added test cases for multiple environments, staging and production.
2. Added test cases for successful p2p connections.
3. Added test cases for archiving

SDK:

1. When user calls get_archive_manifest, it raises error if invalid token is passed in. Token must have moderator role.

[songz]

Hey! I added a fix to a bug problem: Production apps were using the staging.tokbox endpoint to get videos, but it should really be api.tokbox.com

Added test cases for archiving, and also fixed the following:
http://www.tokbox.com/opentok/api/tools/documentation/api/server_side_libraries.html?proglang=ruby

1. Set manifest urls based on production/staging
   https://staging.tokbox.com/hl/archive/getmanifest/archive_ID (for archives created in staging)
   https://api.opentok.com/hl/archive/getmanifest/archive_ID (for archives created in production)

[songz]

1. support for downloadArchiveURL(), which is what the documentation had to improve consistency. Left the previous function alone because to make sure it doesn't break anyone's code.
2. downloadArchiveURL() now returns the direct url for file
3. getId() function implementation
4. Updated documentation to reflect changes.

Thanks Stijnster!