Close #279: "Document" non-stack usage by protecting dtors
Integrate common CMake stuff using git externals
Cleanups
Fix output of received errors
Implement ostream operator for util::Texture
Fix exit after help output
Relax link libraries of ply lib to OpenGL, not Eq
Implement async texture readbacks in plugin
Fix async readback finish by storing zoom factor internally instead of relying on caller to pass the correct value (Fix #287)
Update CMake tree to get working stringify_shaders
Update CMake tree
CR #291
Merge pull request #291 from eile/master

Close #279: "Document" non-stack usage by protecting dtors