implemented aspect ratio calculation
in type bbox calculation implemented
prepared test case to easily create multiple test lines
moved lualib from own folder into Makefile of types
BoundingBox passes centroid test
implemented bounding box for ellipse
Type::Line passes BoundingBox test
fixed compile error due to G++ 4.2 bug
started test case for intype bounding box calculation
added new Lua functions: createGroup, getGroup
