Do not filter out links without a type

[gergely-ujvari]

This is a quick fix for an error I've introduced which can result in searches for uri not bringing back annotations.

Error description

• The annotator client saves document.location.href into the document metadata link without a type
• When saving the document, we remove typeless links, therefore removing the saved document.location.href
• When we search for annotations and construct the search query, we rewrite the uri part of the query and replacing the original uri with the found equivalences.

Therefore if the if we search for an uri of the page and that page doesn't contain a link to itself with a type (common thing among webpages) then the search for that uri will bring back nothing because the document metadata does not contain that uri, and that is not our intention.

Fix #116

[Treora]

I suppose we should then also remove the and 'type' in l in merge_links. Otherwise we return to the inconsistency I pointed at earlier, and the same error will occur but only later, when a document is merged into another.

[gergely-ujvari]

Thanks @Treora you're right.

[gergely-ujvari]

Okay removed it from merge_links too.

[Treora]

LGTM.