Add auto center option, Codeblocks compilation support
Load multiple stl files at once to allow multi-extruder slicing from command line
Merge branch 'master' of https://github.com/Ultimaker/CuraEngine
Merge branch 'master' of https://github.com/Ultimaker/CuraEngine
Fixed raft air gap bug
Merge pull request #95 from repetier/master

Multi-Stl-load, codeblocks support, autocenter, bug fixes