Add grasshopper parameter for plankton mesh

* all credit to Giulio Piacentino and his TurtleMesh project for the param implemetation
    * automatically casts from Rhino mesh
    * native preview
    * reference mesh in Rhino
    * NO serialisation yet
* makes GHMeshToPMesh component obsolete
* rough and ready PlanktonMesh copy constructor (needed for param)
update project files

* reference libraries from "lib" folder
* all outputs to "bin" folder in root
* ignore libraries
update travis-ci config