changelog updated

See merge request !468

Resolve "Export of special characters"

See merge request !467

when pdf encounter SansSerif font it will embed custom font into a pdf that has support for unicode characters

Resolve "Going back to HomePage does not show the map (v12.1.0)"

See merge request !466

changelog updated for version 12.1.0~beta.3

See merge request !465

Resolve "upgrade 3rd party libraries"

Closes #538

See merge request !464