FMSLogo Code

Make the extras compatible with the Portuguese translation of FMSLogo.

Add benchmark results for FMSLogo 6.16.0.

Update the version to 6.16.0 for the next formal release.

Fix a typo.

Add the changes for 6.16.0.

Add some new tests, including tests for CASCADE. Also update to changes in Logolib (now they throw properly localized bad input errors).

Add a test for SETPENCOLOUR, SETSCREENCOLOUR, SETFLOODCOLOUR, PENCOLOUR, SCREENCOLOUR, and FLOODCOLOUR. These are only supported in the English version of FMSLogo.

Fix the "too many inputs" test, now that THROW has a form that takes more than three inputs.

Reformat the code to make it a little easier for me to read.

Replace "pu" with "penup" and "pd" with "pendown" because "pu" means something else on the Portuguese translation of FMSLogo.