Add Tabbed window class to allow swaping panels on tabs
Open config but do not configure windows [also remove config progress bar]
Dont close the dynamic panel objects they will be freeed later
Set window to blank if null to prevent problem if 2 null windows are set in succession
Use sizer->Replace instead of detach/add
Create dynamic panels on the fly when not active destroying previous
Set default value of beenshown
Remove DTSTabPAne class tab traversal is poked
Tab pane returns book controler as panel
Remove API calls dtsgui_closedyn / dtsgui_createdyn
Merge pull request #53 from gregnietsky/master

Various fixups to get tabbed windows more dynamic