Upcoming trip info.
To read, just open the .kml file in Google Earth. It will probably put it in Temporary Places and wrap it with a Trip 2018.kmz.
To commit changes, extract the Trip 2018.kmz as if it were a ZIP file (on windows, just change the extension to .zip and extract normally). On Linux use the unzip utility.
Extract the KML file inside and commit your changes.
If this is too hard maybe I'll write a script to automate some of this. Or maybe putting this is git was a dumb idea and we should just keep emailing each other documents. Or use Google Drive.
(KML is a plaintext file, "Keyhole Markup Language. KMZ is a compressed binary with a KML that has been Zipped).