streamlined LBI calculation  * no more delta LBI  * nodes are alive when in a time window of width LBIBoundaryLayer  * made separate function to set LBI cutoff dates  * branches make contributions to the LBI only when the node is alive,    but the LBI is propagated along them nonetheless  * LBI is normalized to [0,1], adjusted the domain of the colormap    (why not make this an interpolating scale, rather than threshold)  * fixed check for LBI!=undefined in tooltip
streamlined LBI calculation
 * no more delta LBI
 * nodes are alive when in a time window of width LBIBoundaryLayer
 * made separate function to set LBI cutoff dates
 * branches make contributions to the LBI only when the node is alive,
   but the LBI is propagated along them nonetheless
 * LBI is normalized to [0,1], adjusted the domain of the colormap
   (why not make this an interpolating scale, rather than threshold)
 * fixed check for LBI!=undefined in tooltip

doerlbh/Indie-nextflu,doerlbh/Indie-nextflu,blab/stability,doerlbh/Indie-nextflu,doerlbh/Indie-nextflu,fw1121/nextflu,fw1121/nextflu,blab/stability,fw1121/nextflu,blab/stability,blab/nextflu,blab/stability,blab/stability,blab/stability,blab/nextflu,blab/nextflu,blab/nextflu,fw1121/nextflu,blab/nextflu