Refactor and rework element formatting to better support multiple values

Several webform elements support multiple values and the formatting/presentation code for these elements needs to be reusable and maintainable.

Goal

Provide a simple mechanism to output an element's submission value(s).

Notes

• Most elements just need to some very basic formatting. For example, emails and URL should be linked.
• Need to support HTML and plain text formatting.
• Supporting plain text is very important for exporting data.
• Trying to avoid having every submission passed through Drupal theme layer. This would be a major performance hit but might be unavoidable.
• Support multiple values will make it easier for a webform submission to be posted to the Field API.

Tasks

• Refactor OptionsBase to support multiple values.
• Rework formatHtml() and formatText() to route to values or single value.
• Add protected formatHtmlMultiple() and formatTextMultiple().
• Add protected formatHtmlValue() and formatValue().
• Split #format into #format_value and #format_multiple.
• Write update hook to update #format in webforms and admin settings.
• Move OptionsBase code WebformElementBase
• Refactor tokens to support format_value and format_multiple. [webform_submission:values:subject:format_value:format_multiple]
• Update tests.

#format_value

• raw
• value
• link
• etc...

#format_values

• Comma
• Semicolon
• And
• Ordered list
• Unorder list
• Custom

Multiple Elements (#multiple)

• Checkboxes
• Select
• TableSelect
• Toggles
• EntityAutocomplete (#tags)
• ManagedFile