Added cylindrical rendering to the Stars sample, inspired by Robert Hodgin's work and write-up. See: https://forum.libcinder.org/#Topic/23286000001627005

* Tangent fragment shader is on the TODO-list.
Added rendering to FBO for the cylindrical projection. Fragment shader is still on the TODO list, but should not be too hard (it's a lack of time thing).
Added shader - not hugely impressive though. I think I want to alter it a bit.
Working version of cylindrical projection with 270 degree view.
Updated executable.
Updated README.md
Clean-up
Cleaned up project files.
Merge branch 'cylindrical'