Move pagination properties to a separate namespace

[namedgraph]

Pagination can be seen as an extension of basic LDT semantics. Therefore it makes sense to define pagination properties separately.

Template annotation:

• gp:defaultLimit
• gp:defaultOffset
• gp:defaultOrderBy
• gp:defaultDesc

Hypermedia:

• gp:limit
• gp:offset
• gp:orderBy
• gp:desc

[namedgraph]

Moved to dh: namespace