Expose submission data to rules

Right now, submission data is not exposed to rules except by way of token replacement or custom php actions.
This patch exposes submission data in a "first-class" way.

In this patch:

• includes #1948824: Unable to pass submission data into action set component → to fix implementation of hook_rules_data_info(). (This patch will require a re-roll when that gets in.)
• extends hook_rules_data_info() to expose all properties of a submission
• provides better access to submission component values
• class WebformRulesSubmissionWrapper implements RulesIdentifiableDataWrapper to provide entity wrapped access to webform submissions
• New condition "Submission to a particular webform", which works almost identically to "Webform has name", except it relates the submission data to the webform id, instead of text-to-text. (I chose to implement this new condition as separate, rather than combine them, in order not to break any existing rules.) This relation allows for:
• Rules assertion to expose webform components only for the selected webform, instead of exposing all webform components for all selectors (which would not be scalable).

Areas for continued development:
* provides read-only data. setter callbacks not implemented.