- Make the autosegs read-only.

- Derive PClass from dobject.cpp. This has one major ramification: Since the PClass
  is not allocated until runtime, you cannot initialize any static/global data
  structures with pointers to PClasses using RUNTIME_CLASS. Attempting to do so
  will just initialize with a NULL pointer. Instead, you can initialize using
  the address of the pointer returned by RUNTIME_CLASS and dereference that. By
  the time you have an opportunity to dereference it, it will no longer be NULL.
- Sync CmakeLists.txt.
- Random fixes for problems GCC spotted.

SVN r1852 (scripting)

src/thingdef/thingdef_expression.cpp

@@ -50,9 +50,6 @@
 #include "doomstat.h"
 #include "thingdef_exp.h"
 
-int testglobalvar = 1337;	// just for having one global variable to test with
-DEFINE_GLOBAL_VARIABLE(testglobalvar)
-
 // Accessible actor member variables
 DEFINE_MEMBER_VARIABLE(alpha, AActor)
 DEFINE_MEMBER_VARIABLE(angle, AActor)