#86 Huge text bugs

[Thanasis]

I typed some lines of text and then copyed them many times. I guess it maybe was some thousands of lines. Then the application crashes and the window turns black.

However, i tried again and it seems like when the text is over some thousands of lines the editor slows down and needs some more time to execute what the user is typing.

[David Young]

I agree--the program appears to hang for a long time, especially when in syntax highlighting mode. Eventually the lines appeared one batch at a time. I suspect it's reached the limit of the underlying Java Swing component, but there may be optimization to be done in the editor itself as well.