Changed strings in m168

Two new strings in instset - about Thai language support. One string removed from svx/source/dialog.

Annoyance in readme

"HERE is Edward Bear, coming downstairs now, bump, bump, bump, on the back of his head, behind Christopher Robin. It is, as far as he knows, the only way of coming downstairs, but sometimes he feels that there really is another way, if only he could stop bumping for a moment and think of it. And then he feels that perhaps there isn't."

... and the same way we every and every time update the strings in readme when there is no updates really, because of changed date-field which makes whole string new and "fuzzy".

Here it is: "Last updated $Date: 2006/04/28 12:21:31 $". Sometimes I feel that there really is another way for including a date...