Basic import and export function for Events Manager.

Although I never officially released this plugin, it seems to have leaked out and become a part of quite a few websites. I figure that means I ought to get it up and onto GitHub where people can find it and report bugs.

I probably won't be releasing this on WordPress.org because there's already a pretty good plugin for synchronising events between websites:

• Events Manager ESS -- recommended for sychronising events between websites

However, for those who want to continue using this plugin, please feel free to lodge issues and create pull requests. I can't promise that I'll address them in a timely fashion, but I'll try my best.

Donations are always welcome 😃