Add client entity class headers.

* Remove 'isreplay' from player_info_s.

Signed-off-by: aixxe <me@aixxe.net>

include/cstrike/Classes/IClientThinkable.h

@@ -0,0 +1,6 @@
+#pragma once
+
+class IClientThinkable {
+	public:
+		virtual IClientUnknown* GetIClientUnknown() = 0;
+};