FMSLogo Code

Update a bug number to use SourceForge's new numbering scheme.

Rewrite SETPIXEL and PIXEL in terms of platform-independent wxWidgets function calls so that the work on GNU/Linux.

Replace usage of the win32 POINT struct with wxWidget's wxPoint. This makes the code more platform-indepenent although, by itself, doesn't make any new functions availabe on the GNU/Linux build.

Formally thank Peter De Watcher for opening a bug report on gcc
that caused logomath.cpp to fail to compile when optimizations
are enabled. See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71020

Fix a class of warnings that is emitted by recent versions of g++:
warning: invalid suffix on literal; C++11 requires a space between literal and string macro [-Wliteral-suffix]

Fix a macro redefinition warning when compiling on Fedora Core 25.

Fix Bug #485; Remove the synopsis for EDIT taking zero inputs. There is some behavior for this in UCBLogo (re-opening the same file as used in a previous EDIT call), but since FMSLogo also deletes the temp file after closing, this behavior doesn't make sense in FMSLogo. Instead of trying to add it, I decided to document the existing behavior.

Fix Bug #485; Remove an extraneous double-quote for the input to TO in the example code for the EDIT variants. This problem dates back to MSWLogo's manual.

Use the present tense, not the future tense.

Port MESSAGEBOX to be implementing using wxWidgets instead of win32-specific functions so that it's avaiable on GNU/Linux builds of FMSLogo.