FMSLogo Code

Merge in changes to print functions from trunk.

Refactoring: Rename new_line() to print_newline()
This more clearly explains what it does.

Refactoring: Extract function for printing a string.
- remove duplicated logic
- improve performance by replacing ndprintf() when format string had no format parameters

Refactoring: inline print_nobrak()
This removes one of the many confusingly-named print functions.

Merge changes from trunk.

Fix a copy&paste error in a function comment

Add another example to the documentation for BACKSLASHEDP.
This one shows that being between vertical bars isn't sufficent to be backslashed.
The character must also change its semantic meaning.

Extend data range for READCHARS to include control characters.
The Unicode FMSLogo does not prevent ASCII control characters from working correctly.

Remove trailing whitespace

Fix a crashing bug when calling READCHARS with a large number.
The ANSI version implicitly handled overflow by limiting the size of the input
to a signed 32-bit integer, but the Unicode version needs an additional check
as it multipies a buffer size by sizeof(wchar_t).