#62 watches improvements

[Marcello Pietrobon]

The best would be a tree like control so that we can
expand an object. At this moment the 'expand' menu item
fill the watches with so many lines that it becomes
unusable

And to delete all of them is very time consuming
( at that point it is better to deelte everything ), so:

Possibility to select more than one watches line so I
can delete them together

Possibility to save the watches in a file