Twingle API 1.3

Changes since Twingle API 1.2

• [#28] Add parameter for preferred language - by @jensschuppe
• [#36] Use CiviCRM's double opt-in feature for newsletter subscription - by @MarcMichalsky, @jensschuppe
• [#39] Trim project IDs when extracting from profile configuration - by @MarcMichalsky, @jensschuppe
• [#45] Change campaign_id parameter data type and add validation for it - by @MarcMichalsky
• [#46] add a paragraph to warn users against systopia/de.systopia.xcm#78 - by @MarcMichalsky
• [#48] Allow configuring required address comonents - by @MarcMichalsky, @jensschuppe
• [#49] Improve help text for custom fields mapping - by @mariav0, @jensschuppe
• [#51] Update civix-generated code
• [#53] Duplicate XCM-initiated activites for personal addresses - by @jensschuppe