C++11 patchset 9: move hardcoded init parameters to class definitions (part 1) (#5984)

* C++11 patchset 9: move hardcoded init parameters to class definitions

C++11 introduced the possibility to define the default values directly in class definitions, do it on current code

Also remove some unused attributes

* CollisionInfo::bouncy
* collisionMoveResult::collides_xy
* collisionMoveResult::standing_on_unloaded
* Clouds::speed

* More constructor cleanups + some variables removal

* remove only write guiFormSpecMenu::m_old_tooltip
* move header included inside defintions in genericobject.h
* remove some unused since years exception classes
* remove unused & empty debug_stacks_init
* remove unused & empty content_nodemeta_serialize_legacy
* remove forgotten useless bool (bouncy) in collision.cpp code

src/emerge.cpp

@@ -96,12 +96,10 @@ EmergeManager::EmergeManager(Server *server)
 	this->oremgr    = new OreManager(server);
 	this->decomgr   = new DecorationManager(server);
 	this->schemmgr  = new SchematicManager(server);
-	this->gen_notify_on = 0;
 
 	// Note that accesses to this variable are not synchronized.
 	// This is because the *only* thread ever starting or stopping
 	// EmergeThreads should be the ServerThread.
-	this->m_threads_active = false;
 
 	enable_mapgen_debug_info = g_settings->getBool("enable_mapgen_debug_info");