DOType or CDC creation helper wizards

[JakobVogelsang]

As a user of OpenSCD I want to be guided through the process of creating a new DOType element. I want the software to tell me which data objects SDO, data attributes (DA) are mandatory for the data object.

Two wizards are required here:

1. Choose the common data class (CDC) array automatically from IEC_61850-7-3_2007B3. Based on common data class, display possible data objects and data attributes in a selectable list. Mandatory elements shall be preselected.
2. Second wizard is the sDOTypeWizard, dATypeWizard where the user shall have the possibility to select the type. Types shall be preselected based on the information in IEC_61850-7-3_2007B3.

Features

• Array of possible common data classes are based on the definition in IEC_61850-7-3_2007B3
• Array of possible type in sDOTypeWizard and dATypeWizard are based on the CDC type definition in IEC_61850-7-3_2007B3 and defined DOTypes, DATypes in the DataTypeTemplates section
• Progress shall be indicated in terms of how many wizards follow
• When canceling the process, no actions shall be performed. This is especially important when canceling in sDOTypeWizard, dATypeWizard

[JakobVogelsang]

Need #256 first

[JakobVogelsang]

We will not do this for now and will wait for feedback on working with the template's library.