PhotoSell Chroma portable mode

While this file sits next to chroma.exe, PhotoSell Chroma keeps its preferences, brush presets,
crash-recovery autosaves and startup state in the ChromaData folder beside it, and writes
nothing to %APPDATA% or %LOCALAPPDATA%. Copy the whole folder to move PhotoSell Chroma with its settings.

Delete this file to use the normal per-user folders instead: %APPDATA%\Chroma for settings
and %LOCALAPPDATA%\Chroma\Recovery for crash-recovery autosaves. If ChromaData can't be
written (for example on a read-only drive), PhotoSell Chroma says so and uses those folders instead.
