[birt-dev] CheckIn: Fix [Bugzilla] 126103: 'Create template report Item'

["Xiong Zhang" <xiong.zhang@xxxxxxxxxxx>]

-Summary:
Add a name field when create template report item.

- Bugzilla Bug (s) Resolved:
126103

- Description:
I fixed the bug last time, but the UI is not user friendly: When the name exists, close dialog and show the error message.
This time, when the specfied name exists, it'll show an error message and reopen the "Create template report itme " dilalog.

- Tests Description:

- Notes to Build Team:

- Notes to Developers:

- Notes to QA:

- Notes to Documentation:

- Files Added:

- Files Edited:

/org.eclipse.birt.report.designer.core/src/org/eclipse/birt/report/designer/nls/messages.properties
/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/internal/ui/views/DefaultNodeProvider.java