Thin footer, consent passing, bugfixes

Features:

• getConfig() CMP callback function. Returns an object with the current configuration parameters.
• "thin" is a new configuration option for the layout. This option removes the header text and ignores logoUrls in favor of rendering in a much smaller footprint.

Fixes:

• User dictionaries were not loading unless the config option forceLocale was used at the same time. This has been fixed so that publishers do not have to specify a forced locale in order to load custom verbiage.
• Custom purposes were not being rendered on the introduction screen sliders.

Other:

• Checked in the AWS Lambda function code for our serverless consent-passing service. The spec can be found here: https://github.com/InteractiveAdvertisingBureau/GDPR-Transparency-and-Consent-Framework/blob/master/URL-based%20Consent%20Passing_%20Framework%20Guidance.md