Desktop Icons are now accessible

Howdy List,

just to keep you on track:

Good news:
- i got it managed (thanks to gladhorn and hein for assist) to make  
the plasma desktop icons accessible to orca.
currently this lives only on my local branch but i will try to land  
the patch in the next couple of days (next days are busy days for me).  
but after that the desktop icons are fully accessible.

- Keybaord navigation on desktop was fixed in plasma 5.14.1

Bad News:
The F123 team found some issues in kate (text editor) while caret navigation:
1. Arrow up/ down will not interrupt orcas current speech output.  
maybe it looks like to additional content to orca insteed of an line  
navigation. so ctrl needs to been pressed after every line change to  
interrupt.
2. After doing arrow up / down i start to navigate by char (arrow left  
/ right) orca does repeat the previous line once instead of just speak  
the char. this only happen once and directly after an line navigation.