Make sure style is always initialized.

Possible use of uninitialized variable found while reading code.
Update French translation.

Thanks to Michel Leblond.

For #10002.
Fix thubmnails when using embedded jpg thumbs in lt mode
Focus detection: no need to care about rotation
Fix FD for portrait images just after "history stack" -> "discard"
dt_image_altered: just use `if'
Update French translation.

Thanks to Michel Leblond.

For #10002.
dt_dev_distort_{transform,backtransform}_plus: only check for piece->enabled, not module->enabled

WARNING: this might cause some regressions because i have not tested this extensively!
pixelpipe: better status differentiation rather than only a dirty flag
Merge pull request #616 from upegelow/pixelpipe_status

pixelpipe: better status differentiation rather than only a dirty flag
Updated Catalan translation
Merge pull request #617 from josepvm/master

Updated Catalan translation
usermanual: fix for #10009
Merge pull request #584 from LebedevRI/flip-in-iop-flip-not-in-libs

Flip in IOP flip and not upon loading
PREPARE
break
unbreak