Added various misc. stubs and utility code from the Alien Swarm SDK

sp/src/game/server/ai_basenpc.h

@@ -667,6 +667,7 @@ public:
 
 	virtual bool		ShouldAlwaysThink();
 	void				ForceGatherConditions()	{ m_bForceConditionsGather = true; SetEfficiency( AIE_NORMAL ); }	// Force an NPC out of PVS to call GatherConditions on next think
+	bool				IsForceGatherConditionsSet() { return m_bForceConditionsGather; }
 
 	virtual float		LineOfSightDist( const Vector &vecDir = vec3_invalid, float zEye = FLT_MAX );
 
@@ -960,7 +961,7 @@ public:
 	void				RemoveSleepFlags( int flags ) { m_SleepFlags &= ~flags; }
 	bool				HasSleepFlags( int flags ) { return (m_SleepFlags & flags) == flags; }
 
-	void				UpdateSleepState( bool bInPVS );
+	virtual void		UpdateSleepState( bool bInPVS );
 	virtual	void		Wake( bool bFireOutput = true );
 #ifdef MAPBASE
 	// A version of Wake() that takes an activator

sp/src/game/server/baseanimating.cpp

@@ -506,6 +506,11 @@ void CBaseAnimating::StudioFrameAdvanceInternal( CStudioHdr *pStudioHdr, float f
 	float flNewCycle = GetCycle() + flCycleDelta;
 	if (flNewCycle < 0.0 || flNewCycle >= 1.0) 
 	{
+		if (flNewCycle >= 1.0f)
+		{
+			ReachedEndOfSequence();
+		}
+
 		if (m_bSequenceLoops)
 		{
 			flNewCycle -= (int)(flNewCycle);

sp/src/game/server/baseanimating.h

@@ -84,6 +84,7 @@ public:
 	virtual void	StudioFrameAdvance(); // advance animation frame to some time in the future
 	void StudioFrameAdvanceManual( float flInterval );
 	bool	IsValidSequence( int iSequence );
+	virtual void	ReachedEndOfSequence() { return; }
 
 	inline float					GetPlaybackRate();
 	inline void						SetPlaybackRate( float rate );