adds spec for nested set attributes on issues
moves scoped nested set into own module, applies to WorkPackage
internal restructurings of nested_set patch
Re enable additional environment config file

This file is used to load instance specific configuration
like cache store, log file location, etc. so we should load it.
moves after save hooks to work_package
moves code into their own methods
alternate implementation of nested set with root id
renames parent to parent_issue_id for planning element - preliminary
removes reference to plugin from spec
reloads alternate_dates in specs where necessary
reorders and breaks up before filter
adapts form to use journal notes
adapts WorkPackage creation in cukes
removes parent_issue_id from scoped nested_set  as it is no longer necessary - yeah
replaces parent_issue_id with parent_id whereever it was to be found
removes redundant tests
adds documentation
removes method implemented in nested_set
allow hierarchies between Issues and PlanningElements by moving methods up
removes duplcate method, same exists in WorkPackage