#275 CGUIEditBox replacement/overwrite mode using the "Insert" key

[Adam]

In order for me to learn about some of the inner workings of IRRLicht, I decided to do something simple and modify the CGUIEditBox to allow replacement/overwrite functionality with the "Insert" key.

Features

• The User can press the "Insert" key to switch between normal insert mode and replacement/overwrite mode.
• In replacement/overwrite mode the cursor changes to a box which matches the width of the character it is over, because the default font is not monospaced. When not in replacement/overwrite mode the cursor is whatever character was set or the default one.
• In multi-line mode when the end of a line is reached in replacement/overwrite mode characters are appended to that line. This matches the functionality of some of the text editors I use.

I have attached the patch file. Let me know what you think.

[Adam]

In order to test the patch run the User interface example.

[Michael Zeilfelder]

Thanks - worked nicely in all tests I did think off. It's applied in Irrlicht svn r4736.