[patch] very very very very initial caret navigation

[Leo Savernik]

With this huge patch, khtml gets a caret mode (like mozilla's caret mode), 
however, it cannot be activated by gui actions. It compiles against the 
latest CVS (as of 2003-08-09, 4:50 CET DST).

Beware, it is really restricted. Nearly nothing is implemented except very 
basic keyboard navigation. And it's not even working correctly for 
appearently primitive cases (but they aren't if you've seen the 
implementation details)

The reason I'm posting this is to enable the khtml developers to get an idea 
what I'm doing, so please review and comment on the changes.

The next steps are:
1a make caret navigation not suck.
1b make selections cooperate with navigation.
2. implement basic editing.
3. implement drag&drop.
4. implement and fix stuff I've forgotten in the first iterations.