Designer, ChangeClassDialog: formatting, cleanup, add a try - finally block.

git-svn-id: http://svn.freepascal.org/svn/lazarus/trunk@44808 4005530d-fff6-0310-9dd1-cebe43e6787f
Designer, ChangeClassDialog: add space before class name + some layout fine-tuning.

git-svn-id: http://svn.freepascal.org/svn/lazarus/trunk@44809 4005530d-fff6-0310-9dd1-cebe43e6787f
Designer, ChangeClassDialog: reverse the order of ancestor inheritance list. Now starts from bottom (TObject) and grows upwards.

git-svn-id: http://svn.freepascal.org/svn/lazarus/trunk@44810 4005530d-fff6-0310-9dd1-cebe43e6787f