Change from is_linked to links
Bugfix

stops error msg on node creation
Svget/svset update
Bugfix

Check that there is input before accessing it.
Svget/svset
Svget/svset
svget/svset
Fix
Svget/Svset
nodes_s update strategy fix

this collects all node edits and applies them in a better way
more checks in util

linked -> links
made some functions more general
Merge branch 'master' of https://github.com/ly29/sverchok