with Logo syntax, too.

Mutual recursion, for example drawing dragon curve (see in the
unit test of the commit) doesn't need Python syntax any more
to call the function before its definition.

Change-Id: I93426a8c5be394fb4f1203e0490f7fa8d8491597
Reviewed-on: https://gerrit.libreoffice.org/62926
Tested-by: Jenkins
Reviewed-by: László Németh <nemeth@numbertext.org>