Change how open polygons are saved. As std::vector never clears memory and the old implementation could mean a lot of memory was never freed.
Reset start position for new layers
Reset the start position of the path optimizer for each new layer
so that it doesn't double up on the layers, causing problems for
cooling.
Merge pull request #150 from presslab-us/fixpathstart

Reset start position for new layers
Seperate the skin and infill to give them different speeds. Also change the printing order of this to handle pressure differences better. Which should increase print quality on advanced profiles.
Fix the raft printing speed.
Fix wrong pull-request #134