Merge remote-tracking branch 'origin/topic/timw/266-namespaces'

Merge adjustments:

- Preserved original `base_type_no_ref` argument type as ::TypeTag
- Removed superfluous #pragma guard around deprecated TableVal ctor
- Clarify NEWS regarding MetaHook{Pre,Post} deprecations
- Simplify some `::zeek::` qualifications to just `zeek::`
- Prefixed FORWARD_DECLARE_NAMESPACED macro with ZEEK_

* origin/topic/timw/266-namespaces:
  Disable some deprecation diagnostics for GCC
  Rename BroType to Type
  Update NEWS
  Review cleanup
  Move Type types to zeek namespace
  Move Flare/Pipe from the bro namespace to zeek::detail
  Move Attr to the zeek::detail namespace
  Move Trigger into the zeek::detail namespace
  Move ID to the zeek::detail namespace
  Move Anon.h into zeek::detail namespace
  Mark all of the aliased classes in plugin/Plugin.h deprecated, and fix all of the plugins that were using them
  Move all of the base plugin classes into the zeek::plugin namespace
  Expr: move all classes into zeek::detail
  Stmt: move Stmt classes into zeek::detail namespace
  Add utility macro for creating namespaced aliases for classes

src/Tag.h

@@ -3,14 +3,15 @@
 #pragma once
 
 #include "zeek-config.h"
-#include "IntrusivePtr.h"
-
-#include <string>
 
 #include <stdint.h>
+#include <string>
+
+#include "IntrusivePtr.h"
+#include "util.h"
 
 class EnumVal;
-class EnumType;
+ZEEK_FORWARD_DECLARE_NAMESPACED(EnumType, zeek);
 
 /**
  * Class to identify an analyzer type.
@@ -115,10 +116,10 @@ protected:
 	 *
 	 * @param etype the script-layer enum type associated with the tag.
 	 */
-	const IntrusivePtr<EnumVal>& AsVal(const IntrusivePtr<EnumType>& etype) const;
+	const IntrusivePtr<EnumVal>& AsVal(const IntrusivePtr<zeek::EnumType>& etype) const;
 
 	[[deprecated("Remove in v4.1.  Use AsVal() instead.")]]
-	EnumVal* AsEnumVal(EnumType* etype) const;
+	EnumVal* AsEnumVal(zeek::EnumType* etype) const;
 
 	/**
 	 * Constructor.
@@ -131,10 +132,10 @@ protected:
 	 * @param subtype The sub type, which is left to an analyzer for
 	 * interpretation. By default it's set to zero.
 	 */
-	Tag(const IntrusivePtr<EnumType>& etype, type_t type, subtype_t subtype = 0);
+	Tag(const IntrusivePtr<zeek::EnumType>& etype, type_t type, subtype_t subtype = 0);
 
 	[[deprecated("Remove in v4.1.  Construct from IntrusivePtr& instead.")]]
-	Tag(EnumType* etype, type_t type, subtype_t subtype = 0);
+	Tag(zeek::EnumType* etype, type_t type, subtype_t subtype = 0);
 
 	/**
 	 * Constructor.