TL;DR: Mashable readers who register with Nomad can score 30% off select Nomad eSIM plans with code MASH30. Summertime is just around the corner, and you know what that means: it's time to travel . If you're planning some fun vacations in the coming months, or maybe you're someone who has to travel frequently for work, international data is the last thing you want to be worrying about. That's where Nomad comes in handy with its helpful eSIM data plans , and Mashable readers can score a deal on select plans right now. Registered Nomad users can score 30% off Nomad eSIM data plans when using the code MASH30 at checkout. With over 200 locations worldwide to choose from, making use of this offer is an excellent way to save some cash ahead of your next trip. There are a few things to keep in mind, though: This offer only applies to registered users and does not apply to Day Plans or plans that cost less than $5. It's also not eligible for add-on data.…