Filter out BugInstances from history output that are "dead" (i.e. the "last" attribute is specified).  Also, avoid NaNs with more checking.  This fixes sourceforge issue [ 1876584 ] two default.xsl flaws.
Filter out BugInstances from history output that are "dead" (i.e. the "last" attribute is specified).  Also, avoid NaNs with more checking.  This fixes sourceforge issue [ 1876584 ] two default.xsl flaws.

git-svn-id: e7d6bde23f017c9ff4efd468d79d66def666766b@9273 eae3c2d3-9b19-0410-a86e-396b6ccb6ab3

sewe/spotbugs,spotbugs/spotbugs,KengoTODA/spotbugs,johnscancella/spotbugs,sewe/spotbugs,spotbugs/spotbugs,spotbugs/spotbugs,sewe/spotbugs,johnscancella/spotbugs,KengoTODA/spotbugs,sewe/spotbugs,johnscancella/spotbugs,johnscancella/spotbugs,spotbugs/spotbugs,KengoTODA/spotbugs,KengoTODA/spotbugs,spotbugs/spotbugs