from the current Model/ModelObjects.
Fixed a possible race condition in updating Print::m_placeholder_parser
with the proposed filename / filename base.
Improved documentation (source code comments).
template.
Reworked naming of the plater exports to not use the output file name
template, but to derive the file name from the first printable object's name.
Fixed error handling: Reimpemented the Perl's "eval" blocks
as try / catch blocks.
