CDClient cleanup and optimization (#1023)

* CDClient cleanup and optimization

- Use static function to get table name
- Remove unused GetName function
- Replace above function with a static GetTableName function
- Remove verbose comments
- Remove verbose initializers
- Remove need to specify table name when getting a table by name
- Remove unused typedef for mac and linux

* Re-add unused table

Convert tables to singletons

- Convert all CDClient tables to singletons
- Move Singleton.h to dCommon
- Reduce header clutter in CDClientManager

dDatabase/Tables/CDObjectsTable.cpp

@@ -43,14 +43,6 @@ CDObjectsTable::CDObjectsTable(void) {
 	m_default.id = 0;
 }
 
-//! Destructor
-CDObjectsTable::~CDObjectsTable(void) {}
-
-//! Returns the table's name
-std::string CDObjectsTable::GetName(void) const {
-	return "Objects";
-}
-
 const CDObjects& CDObjectsTable::GetByID(unsigned int LOT) {
 	const auto& it = this->entries.find(LOT);
 	if (it != this->entries.end()) {