Switch property for Braille text

[ChristophEwertowski]

Resolves #827

[ChristophEwertowski]

@fsteeg : The icon for "Blindendruck" doesn't appear in test.lobid.org/resources/search. The resources.conf is adjusted and the test resource TT001210514 has the right icon and label. What did I overlook?

[fsteeg]

I've opened #885 for the underlying label lookup issue.

[dr0i]

Assigning @acka47 , please have a look at the Files changed. As there are more added definitions than just the Braille one , and if you agree, we could merge this already to have the data in our index. Icons and other frontend issues can be solved later.

[TobiasNx]

@acka47 This PR is quite old and I think we should close it, since it only changes the old morph transformation.

The issue still seems to be valid, the URI for BrailleBook ( http://purl.org/library/BrailleBook) seems to be not resolvable.
@ChristophEwertowski changed the property first to a GND property and then to a lobid vocabs concept "http://purl.org/lobid/lv#Braille". I dont know if we still want to change this but then we should do this in a new PR.

Additionally the changes in cfe256e seem to be valid and could be cherry picked, since they add missing labels to the context labels file.