pwstrorage: naieve password storage backend autodetection

this should probably be replaced with something a little
more intelligent at some point in the future.
atrous: cleanup presets

most of these presets represent subtler or stronger versions, that
can be achieved by mixing to 0.5 or 2.0

naming was slightly adjusted to get better (alphabetic) sorting
OSX packaging: minor change to make-app-bundle
Merge branch 'master' of https://github.com/darktable-org/darktable
letsgofloat: new IOP
Temperature iop: Fix process (Bayer)
Temperature iop: Fix process (X-Trans)
Invert iop: Fix output_bpp()
Invert iop: Fix process (Bayer)
Invert iop: Fix process (X-Trans)
letsgofloat iop: allow tiling
letsgofloat iop: implement OpenCL kernel!
Temperature iop: Fix process_cl
Invert iop: implement OpenCL kernel (1f)!
Invert iop: implement OpenCL kernel (4f)!
iop_dependencies.py: add letsgofloat
Run iop_dependencies.py after merge!