Prompt for class name when creating a class
Add right-click menu to classes

Allows renaming, deleting, adding methods and members
Prompt user to enter a name for new Diagrams
Merge remote-tracking branch 'origin/master' into ClassDialog
Handle right-click menu on MacOS X
fixed methods and members, being drawn, and also fix a warning
Rearrange where the popup menu stuff is created
Merge pull request #20 from Zedzap/ClassDialog

Add right-click menus