Pressing E while typing the train limit should close the window instead of setting it to zero

[lazy_londor]

TL;DR

Currently, if you press E after typing the train limit then the train limit is set to zero instead of closing the window. The same happens for setting the train priority. I think that any text field that can only accept numbers should close/confirm the window if the user presses E.

What?

Steps:

• Select a train stop
• Type 1 into the train limit field
• Press E on the keyboard
• The train limit is currently set to zero, but I think it would be better to close/accept the number I entered.

Why?

A significant number of windows can be closed by pressing E. There is no reason to enter a non-numeric character in the train limit field so pressing E while a number only text field is in focus shouldn't be a problem (that I'm aware of).