adds dist and cluster
adds CLUSTERING_THRESHOLD calculation
adds screenX and screenY temporarily
adds grouping members to overlayitem
adds getGroupSet
fixes threshold's proportion of the screen, adds currentGroup
fixes getting center by using angles and not means (duh)
adds getThreshold
adds temp special overlay for cluster markers
chage location of log point so that it actually asserts that the marker has been loaded
fixes initialization of cluster overlay
changes default pivoting point to center-center
generates marker with cluster
adds method to remove a marker from the default itemized overlay
not drawing if item is currently inside a cluster
adds invalidate to hotspot setting
adds property to check if clustering is enabled for this overlay
sets property on cluster match
fixes strange lines missing. probably shouldn't merge this to master
uses PointF instead of dist, removes dist