HTTP url output support

[CaitlinOCallaghan]

Based off of Joey Parrish's HTTP Upload commit

Feature

• Allow users to specify a HTTP url as an output
• Segments and manifests will be uploaded to the specified url via HTTP PUT
• Urls ending with a '/' will have the slash removed to prevent issues with Google Cloud

Testing

• Added unit tests to check for config compatibility errors, such as specifying an HTTP url output with a "multi_period_input" and with "segment_per_file" set to false

Shortcomings

• The multi period input list feature is currently structured to use the local file system and does not easily support HTTP uploads. This must be addressed as the multi period input feature continues to evolve, @meryacine.
• The HTTP upload feature does not make sense if used with a cloud url, and although there is an error check for this, there is no unit test. The cloud url unit test would have required a mock bucket to pass the cloud url validity checks. Because of the work involved in writing a mock bucket and the future (and hopefully soon) removal of the CloudNode, it was decided that forgoing this particular unit test was okay.

[joeyparrish]

style nit: indent +2 spaces here

[CaitlinOCallaghan]

Fixed! :)

[joeyparrish]

Doh! Sorry I overlooked your last changes on this. Merging now!