add basic comment node type
show comment on mouse over comment nodes
user node parameter setter in runtime
display comment next to comment node

either right, if there's enough space, or left of the node
until paperjs supports AreaText, a more beautiful solution is a lot of work,
since we'd have to compute the space occupied by the text manually.
always render comment text of comment node
agent gets removed after its death
Update UI, if nodenets are added on serverside
update displayed version number
attempt to fix worldobject rendering
less nervous nodenet-state-polling
prevent agent from getting stuck.
comment nodes only consist of the comment itself

also, yellow background, preserve select and drag functionality
fix empty comments, comment d&d
prevent comment jumping
Merge pull request #39 from Doik/comments

Comment nodes!
Merge pull request #40 from pBartels/master

agent gets removed after its death
add test for unregistering agent on death

also, remove redundant line
remember section collapse state in cookie
fix adding slot monitor
basic tessts for adding, deleting monitors. tbc