Build an offgrid executable identical to raspistill.
Add tclled.{h,c} files and #include them into OffGrid.c.
Always use OpenGL, always.
Always capture GL frame-buffer instead of camera output.
Make offgrid the default GL scene.
Remove some unused functions and a variable.
Rename some remaining occurrences of raspistill to offgrid.
Remove support for timelapse mode.