Implement an issue cache to prevent multiple RedmineInstances to be created for the same issue id
Wireup the redmine properties to the netbeans APIs (Duedate is part of issue and schedule date can be projected onto start date)
Add freshly created issues to the issue cache (additional change: dont' set newly created issue data into redmine issue (causes potential nullpointers going further)
Handle the case where issueData is not yet set in RedmineIssue for getDueData/setSchedule/getSchedule
Fire event on data change (fixes entry frame for new issue not changing after save)
Merge master into implement_scheduling

Conflicts:
	dev/redminenb/src/main/java/com/kenai/redminenb/repository/RedmineRepository.java
Merge pull request #7 from matthiasblaesing/implement_scheduling

Implement issue scheduling