physical_printers.
Updated the snapshots dialog to display sla_print and sla_material.
Updated the snapshots dialog to display physical_printer instead of
printer if the physical_printer key is nonempty.
The "physical_printer" key was moved from [extras] to [presets] section
of PrusaSlicer.ini
profile. The matching has the following priority:
1) Compatible Print profile with the same logical name aka alias.
2) Prefered Print profile with the same layer height.
3) Compatible Print profile with the same layer height.
4) Prefered Print profile.
5) Any compatible profile.
The same logic applies to the selection of Filament profile, only
a filament_type is compared, not the layer height.
+ fixed a bug : Case sensitivity of printer's name wasn't check during the adding of a new printer,
as a result in printers list was appeared both of printers (ex. "YuSanka" and "yusanka"), but related file was just one.
1) All slicer's exceptions are now derived from Slic3r::Exception.
2) New exceptions are defined for slicing errors.
3) Exceptions are propagated to the Plater to show.
It remains to modify the slicing back-end to throw the new SlicingError
exceptions instead of std::runtime_error and to show the other exceptions
by a message dialog instead of a notification.
