Use fixed width integer types in Compiler

- Contributes to #535
- Contributes to #531
- Also address many code analysis issues from VS19 in-IDE parser
  - e.g. Use of enum class in preference to unscoped enums
- Define specific integer types (using enum class) for IPs and text positions to help identify
errors

Core/DolphinVM/Compiler/Compiler.idl

@@ -144,7 +144,10 @@ library CompilerLib
 		CInfoLast = CInfoHardBreakpoint
 	} FirstAndLastCodes;
 
-	typedef enum FLAGS {Default=0x00, SyntaxCheckOnly=0x02, NoOptimize=0x08, TextMap=0x10, TempsMap=0x20, DebugMethod=0x40, Boot=0x80, ScanOnly=0x100, Interactive=0x200, SendYourself=0x400} FLAGS;
+	cpp_quote("#define class_CompilerFlags class CompilerFlags")
+	typedef enum class_CompilerFlags
+	{Default=0x00, SyntaxCheckOnly=0x02, NoOptimize=0x08, TextMap=0x10, TempsMap=0x20, DebugMethod=0x40, Boot=0x80, ScanOnly=0x100, Interactive=0x200, SendYourself=0x400} FLAGS;
+	cpp_quote("#undef CompilerFlags")
 
 	[
 		object,

Core/DolphinVM/Compiler/CompilerSupport.cpp

@@ -14,7 +14,7 @@ be thrown away eventually, or perhaps compiled into a separate DLL.
 
 #include "..\VMPointers.h"
 
-POTE Compiler::NewCompiledMethod(POTE classPointer, unsigned numBytes, const STMethodHeader& hdr)
+POTE Compiler::NewCompiledMethod(POTE classPointer, size_t numBytes, const STMethodHeader& hdr)
 {
 	//_ASSERTE(ObjectMemory::inheritsFrom(classPointer, GetVMPointers().ClassCompiledMethod));
 	// Note we subtract