The main reason to have this is so renders can be scripted to write to a specific file without having to do annoying tricks like set a dummy start/end frame range, render an animation and work out the current frame image will be written to, then rename after rendering.
Also made some 'char *' args into 'const char *'
the render engine assumes the RenderResult's rectf is not in linear color space when color management is disabled so the sequencer and opengl render need to follow this else it results in dark images.
When enabled the context's 3D view will be used for rendering.
When disabled a camera view with solid draw mode will be used.
(Needed for batch rendering out animation previews without having to worry about an existing 3D view, its local layer locking and draw type)
Only source/blender/editors/ dir, should not give errors on different platforms
Only removing: UI_*.h, ED_*.h, WM_*.h, DNA_*.h, IMB_*.h, RNA_*.h, PIL_*.h
unrelated changes that ended up being more trouble to commit separate...
- removed BLI_split_dirfile(), was nasty, occasionaly modifying the source string, it could create directories and used the $CWD in some cases. was only used in 2 places in filesel.c, if this gives problems can address without bringing back this function.
renamed BLI_split_dirfile_basic --> BLI_split_dirfile
- view3d_operator_needs_opengl was being called for offscreen render when it wasnt needed.
