Write comments without stopping execution

[Zomis]

At the moment all edits made to the code area will enforce the program to be stopped, it would be better if code execution can continue as long as non-code stuff is modified.

There are a few options for how to handle modifications:

• Code that is added is not used until the file is saved (code can be marked with different background color to indicate this)
• Code that is removed probably need to apply changes directly (or just mark code with different background color?)
• If code is modified, show a "Don't ask this again" dialog about if the execution should be stopped
• Do not allow modifying the code while program is running, only allow edits to comments