planning/berlin-2018: [Participants] add self

Author: tantek

planning/berlin-2018.txt

@@ -44,6 +44,7 @@ And please add 'yes' to the TYPO Labs column if you'd be interested in attending
 | Rossen Atanassov | | | | train | Yes |
 | Shane Stephens | | | block | | |
 | Tab Atkins | | | block | | |
+| Tantek Çelik | | | AirBnB? | | Maybe |
 | Vladimir Levantovsky | | | block | | Yes |
 
 === Observers ===