• add source for AWB Oldenburg, Germany (thanks @chbartsch)
• add source for AWB Esslingen, Germany
• ignore special events for brisbane.gld.gov.au (thanks @trstns)
• add unique_id to calendar
• add source for AWB Limburg-Weilburg, Germany (thanks @AtryFox)
• add source for VA Syd, Sweden (thanks @stefanodesjo)
• fix source Christchurch City Council, New Zealand (thanks @codyc1515)
• add source for WSZ Moosburg (thanks @dweinber)
• add source for Ipswich City Council, Australia (thanks @tonymyatt)
• add source for A-Region, Switzerland