AP_Scripting: stop libraries including AP_Logger.h in .h files

AP_Logger.h is a nexus of includes; while this is being improved over
time, there's no reason for the library headers to include AP_Logger.h
as the logger itself is access by singleton and the structures are in
LogStructure.h

This necessitated moving The PID_Info structure out of AP_Logger's
namespace.  This cleans up a pretty nasty bit - that structure is
definitely not simply used for logging, but also used to pass pid
information around to controllers!

There are a lot of patches in here because AP_Logger.h, acting as a
nexus, was providing transitive header file inclusion in many (some
unlikely!) places.

libraries/AP_Scripting/lua_repl.cpp

@@ -10,6 +10,8 @@
 #include "lua/src/lauxlib.h"
 #include "lua/src/lualib.h"
 
+#include <AP_Logger/LogStructure.h>
+
 #if !defined(LUA_MAXINPUT)
 #define LUA_MAXINPUT    256
 #endif

libraries/AP_Scripting/lua_scripts.cpp

@@ -16,6 +16,7 @@
 #include "lua_scripts.h"
 #include <AP_HAL/AP_HAL.h>
 #include "AP_Scripting.h"
+#include <AP_Logger/AP_Logger.h>
 
 #include <AP_Scripting/lua_generated_bindings.h>