Rework Marshalling Form: Describe each blazon in a new form

Currently, marshalling is described in the same form. With the changes from #8 (closed) and #74 (closed) the entry form is now much too slow. Therefore, implement the following changes:

• Marshalling should no longer work through partial forms, that are loaded into rsp:CoatOfArmsForm.
• Instead it should only be possible to "link" to a marshalled coat of arms with the URI of another blazon.
• For better utility, each segment in rsp:CoatOfArmsForm where marshalling is possible, should contain a button to add/go to the linked coa description
• this opens a new tab(!) in the browser with the same form as rsp:CoatOfArmsForm, BUT this form must only contain the entry form for blazon -- not any data on the representation
• when one has entered part of a marshalled coa with the new form, the new URI of the new coa is displayed. This must then be copied into an entry field in the "old" coa entry form

Implicitly, this means that the new coa entry form is not linked to the user who entered the blazon. This is in accordance with how the ontology is designed, since the description act of a representation is linked to a user, but not the blazon.