Homoclinic initialization

For homoclinics the same problems occur as with limit cycles, a homoclinic continuation can't be done by just calling the continuer as
[x,v,s,h,f]=cont(@homoclinic, x0, v0, opt)
The homoclinic curve file has to know Also an initial cycle x0 has to be known. All this information can be supplied using an initializer. All initializers return an initial cycle x0 as well as its tangent vector v0.

For homoclinic-to-saddle-node orbits, the user needs to replace Hom with HSN in the above commands. Note that there are no HSN orbits emanating from a BT point, so only the initializers from a limit cycle and a previously computed HSN are available.