[Lazarus] Copy to clipboard from synedit

[Michael Van Canneyt]

Hi,

If you copy text to the clipboard in synedit, an extra #0 character is
copied at the end. It does not happen for other controls I tested.

I tested on Linux, 64-bit GTK2, but I suppose it will be the same for other
platforms/widgetsets.

This can be seen easily: copy some source text in the IDE. Paste it in
libreoffice writer. You'll get a # character at the end.

Some programs handle it well (xclip), some do not. 
I've also had problems copying text e.g. to a browser.

I tested on Linux, 64-bit GTK2, but I suppose it will be the same for other
platforms/widgetsets.

Michael.