FMSLogo Code

Add missing #include to fix build breaks when not compiling with a precompiled header.

Add additional test variations for parsing numbers.

Fix bug #338; SETACTIVEAREA now throw errors when given non-integer values.

This required a little refactoring of the argument and conversion logic to provide an "integer only" argument checker.

This revision also includes a regression test that SETACTIVEAREA persists the new settings to the configuration.

Add function comments to numberp()

Add a function to uninitialize the DLL subsystem. This cleans up memory which a Logo programmer may have forgotten. It also fixes an assert failure in the case when DLLFREE is not called.

Enable the procedures in term.cpp under WX_PURE.
This unblocks running the screen.lgo tests on GNU/Linux.

Use the same flags for CCommanderDialog, regardless of platform.
I don't remember why different platforms had different flags, but I
expect that I had misread some documentation that wxSYSTEM_MENU didn't
exist on UNIX.

Don't register an event handler for EVT_STC_CLIPBOARD_PASTE on
wxWidgets versions less than 3.1.0, where it is not defined. This
unblocks further development for Fedora Core, whose most recent
wxWidgets library is 3.0.2.

Remove a "bool Padding" in the Turtle struct that wasn't referenced by the code. I assume this was added so that an array of Turtle would be word-aligned for performance, but compilers do this anyway and having an explicit field for padding only risks making the structure larger than needed.

Replace comments that referred to the "OWL-based version of FMSLogo" with "MSWLogo" or simply remove them. This was done to remove confusion for anyone reading the code, since the OWL-based version of FMSLogo no longer exists.