Plugin library caching.

Existing plugin system has one big flaw. The Engine don't have any data about loaded plugin libraries.

Solution

Let's make a new class that represents loaded plugin library:

class CPluginModule : public CResource
{
  public:
    HINSTANCE _hiLibrary;

Then create own CResourceStock for them:

class CResourceStock_CPluginModule : public CResourceStock
{

Let's rewrite CPluginClass like this:

class CPluginClass : public CResource 
{
  public:
    CPluginModule *_pModule; // Replacement for 'HINSTANCE _hiLibrary;'

So if we want to load CShaderClass or CEntityClass - we should obtain the CPluginModule.