iop/soften: Drop locals range and hr, and fixup comment

hr is always equal to radius, and range is only used to calculate hr.
iop/soften: Use SSE for inner blur loop
iop/soften: Apply OpenMP to inner blur loops
src/iop/soften: Use SSE in final output stage
iop/soften: Use _mm intrinsics instead of operator overloading for compatibility
Revert "views: Update dt_view_get_image_to_act_on for zoom==1 & full_preview."

This reverts commit ebcc7c27edb72c190b3392e254395c9d452f877c.

This commit changed the size of the settings struct stored in db so we
drop it when loading an old db.
TODO:
- fix this commit (lemagoup is already working on it)
- stop writing this stuff to db
Fix compilation on some system.
[l10n] Swedish update: lowcasing spree translated
Italian translation updated for the new option 'expose-status'
connect key accel callbacks to bauhaus sliders (complements commit 09a02f4093f52)
Merge remote-tracking branch 'bruceg/soften-speedups'
Add lift/gamma/gain module

I am neither sure whether the math could be improved nor the place in
the pipe is ideal. Please test and expect changes that could break your
history stacks.
masks: add ellipse shape

GUI wise this should be mostly straightforward. to rotate the ellipse
CONTROL-Click on the form.
Merge pull request #268 from bartokk/master

Italian translation updated for the new option 'expose-status'
Update French translations.
Revert "Fix compuation of radius, fix drawing arrow to circle and not center."

Keep the const modifier.

This reverts part of commit a8038e5caa36d5788c9b6186d833ee51c8ff3eaf.
Use dt_masks_edit_mode_t enum where expected.
masks: correctly initialize form_gui->edit_mode: fixes regression when removing shapes
masks: fix bug in last commit
Revert "masks: fix bug in last commit"

This reverts commit df0e4c63c780884cd58131a043f443e77e60670d.

this and the preceding commit lead to crashes. we need to find an alternative
to fix the issue with deleting shapes.