[PROPOSAL] Save temp file, so you can recover from it in case of crashes

[raffaem]

The vast majority of editors periodically save a copy from time to time in a temporary file, so that in case the application crashes (for example, if it crashes when the user click "Save"), he will not lose his work.

Apparently ReText doesn't, and even it crashes, the user will lose its work.

It would be useful for ReText to write the changes to a temporary file (maybe in the same folder of the original file) from time to time, so you can recover from errors.

[hydrargyrum]

#593 is another (less involved) option for not losing work in case of error