move search result string to admin js

• location seems more adequate
test and fix if it is used externally

• when links are handled in a different context like the SchulCMS plugin
	then the link_details are opened without being initialized in this content
	so the fields that are not required in externally managed context have to be hidden in initialize and in fill_data
test and fix if it is used externally

• when documents are used in a different - externally managed - context like f.e. the SchulCMS plugin
	then the document_details are opened without being initialized in this context
	so the fields that are not required in externally managed context have to be hidden in both initialize and fill_data
• check if fields are posted in save
• improve language strings and detail layout