FMSLogo Code

Fix some missed translations of "in" -> "en" in the Spanish manual.
For some reason, the spell checker in my LibreOffice doesn't flag "in" as a misspelling.

Document the interaction between Unicode and opening the clipboard as file:
- The clipboard must contain text when it's opened for reading.
- In binary mode, the existing text is encoded in UTF-8 and all text written must be encoded in UTF-8.
- Even in binary mode, you can only write text to the clipboard.

Allow all-caps PUERTO in error-processing.xml
This was added to the documentation when the I/O port API was changed from showing message boxes to throwing errors.

Allow the word MESSAGE in error-processing.xml
It was added when the MCI and Network error dialog boxes were converted to error codes.

Rework the unicode LABEL tests so that the text lines up.
This makes the text easier to read.

Clarify the wording of some comments

Fix some typos in comments

Enable screen repainting in zoomed modes on GNU/Linux.
Without this, the screen was completely blank when zoom.

Remove trailing whitespace

Replace the (incorrect) Spanish implementation of ARCOELIPSE2 with a COPYDEF.
This extends the fix for bug #494 to the Spanish version of FMSLogo.