[Files] Sanitise Assignment titles on input

[Mikee]

Problem statement:

When pasting assignment titles from internally generated documents (typically word), special characters like the em-dash are not sanitised, leading to gradebook export display issues.

Proposed solution:

Sanitise all title inputs on submission, to prevent non-formatted text outputs (like the CSV Gradebook export) from attempting to display nonstandard character encodings. This has lead to several instances that I've escalated to engineering where the gradebook export cannot be reimported, and throws an error. Viewing the file shows nonstandard characters and CR/LR characters that are not stripped from the originating source preventing display in excel, and sometimes precluding reupload when not modified.

User role(s):

admin,instructor

[Mikee]

and here it is as displayed in the subject web view:

[Mikee]

Might be an idea to filter "inappropriate emoji" here as well...