[sldev] Patch - Cursor keeps desired X position in Text Editors

[Tofu Linden]

Zi Ree wrote:
> Navigating the cursor up and down through a text editor makes the cursor jump 
> to the end of line when the line is shorter than the previous one. Moving 
> back to the previous line should restore the previous cursor position as 
> well. The cursor should always try to keep its X position, regardless of any 
> shorter lines traveled through in the meantime.
> Jira Entry: https://jira.secondlife.com/browse/VWR-682

Committed - thanks!

- Tofu