ADDED: an expected XML file for tasks API and an appropriate test in TaskScannerPluginTest (equivalent to the API test in FindbugsPluginTest)
ADDED: new TaskScannerPluginTest case which deals with multiple task tags
ADDED: new TaskScannerPluginTest case which deals with fixed / closed warnings.
CHANGED: amended AbstractCodeStylePluginAction class to get contents from the "Fixed" tab and introduced a (more or less) generic function to map table cells to a map
ADDED: a variant of fileset1 which contains less open tasks