Continuation Core and Toolboxes (COCO) Code

changes for testing boundary handling

fixed bug for constant components

save bifurcation diagram only when solution has label (much faster now)

added function for testing handler for boundary events

- added handling of initial points on boundary
- we account for zeros in opts.cont.ItMX

Minor cosmetic fix

Corrected comparison in printing of headline for Newton iteration.

temporary: small workaround problem with initial points on boundary

- added algorithm for multi-valued events
- we can now specify a function as event name,
this function is used for communicating actions
to be taken on event groups (event handler)
- moved computation of initial point to cover1d
- added check that initial point is interior point
- modified example coneA to illustrate multi-valued
events and reverse communication via event handler